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259 Cards in this Set
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- 3rd side (hint)
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Difference between primary and secondary amenorrhea?
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Primary Amenorrhea
• Lack of: • pubertal development at two standard deviations above the mean age for the general population of the geographical area • breast development by age 14 • menses by age 16 or menses 4 years after thelarche. Usually it only takes 2 years between thelarche and menses. Secondary - no menses for >6 mo in a girl who was previously menstruating. |
Amenorrhea and Infertility
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What do the following words mean in relation to puberty and development?
-Thelarche -Pubarche |
Thelarche = First development of breast tissue
Pubarche = First development of pubic hair |
Amenorrhea and Infertility
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Important parts of the Hx when someone comes in with amenorrhea?
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• Birth / Developmental Hx (Milestones)
• Pubertal changes • Symptoms: • Cyclical abdo pain (outflow tract obstruction) • Hyperprolactinemia: headache, visual disturbances, galactorrhea • Hypothyroidism: cold intolerance, dry hair, constipation, weight gain, fatigue • PMH: chronic disease, operations, chemotherapy, radiation therapy • Medications • Lifestyle: exercise, stress, diet, illicit drugs, sexual activity • Family Hx |
Amenorrhea and Infertility
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What are the three broad categories of causes of amenorrhea and what do the FSH levels look like in each?
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Usually FSH and LH cycle together, although there are some cases where that doesn't happen.
1. Central (Hypothalamus/Pituitary) - Hypogonadotrophic (low FSH) 2. Peripheral (ovaries) - Hypergonadotrophic (high FSH) 3. Outflow tract (Ut, Cer, Vag) - Eugonadotrophic (Normal FSH) |
Amenorrhea and Infertility
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What are the big causes of Hypogonadotropic Hypogonadism (hypothalamus/pituitary dysfxn)?
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Primary
#1 cause - idiopathic #2 cause - Kallman's (CNS - will cause you to lose sense of smell) Secondary - Hypothalamic dysfunction *(FSH may be N). Things that cause hypothalamaic dysfxn include marijuana (decreases GnRH levels), stress, exercise, chronic disease. - Sheehan’s syndrome (pituitary infarction post-partum). - Endocrine: Hyperprolactinemia, Hypothyroidism - Pregnancy! |
Amenorrhea and Infertility
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What is Kallman's Syndrome?
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X-linked
• isolated GnRH deficiency → failure of migration of GnRH neurons from the forebrain. Occurs during development. • Symptoms - anosmia (aplasia olfactory bulbs; lose sense of smell), short 4th metacarpals, syndactyly (fingers or toes fuse together), midline skeletal defects (cleft palate, unilateral renal agenesis), lack of puberty |
Amenorrhea and Infertility
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Four big causes of hyperprolactinemia?
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Pituitary Lesion (only 25% of the time)
Drugs Hypothyroidism Renal Failure |
Amenorrhea and Infertility
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Big causes of Hypergonadotropic Hypogonadism?
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Hypergonadotropic Hypogonadism means your gonads themselves are not working, therefore elevated FSH.
Primary (Gonadal Dysgenesis - Always familial, all due to karyotype changes) - Turner's is the biggest one here. Can be XO (50%) or can be a mosaic where you present someone along the continuum of Turner's. Usually amenorrhic, but can have breast development, etc. If typical Turner's though, no puberty. XO (50%), XO/? = mosaic (25%), 46 XX- abn X (25%) - Pure Gonadal Dysgenesis (like Perrault syndrome or Sweyer’s syndrome), or can be 17-hydroxylase def. Secondary (or Primary) - Premature Ovarian Insufficiency (POI) - Polycystic Ovarian Syndrome/disease: ↑ LH/FSH ratio >2 |
Amenorrhea and Infertility
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What is premature ovarian insufficiency? Causes?
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Also called early menopause. When a woman's ovaries stop working before age 40. Occurs in 1-3% of women. Can be:
idiopathic (biggest cause), genetic (eg. Turner's mosaic), Autoimmune (SLE, diabetes), Ovarian damage (chemotherapy, radiation, surgical) Infections (mumps) |
Amenorrhea and Infertility
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What are the main outflow tract abnormalities?
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Primary
- Outflow Tract Obstruction - Hymen - Imperforate - Vagina - Transverse Septum (complete band of tissue that closes off the vagina) - Cervix – Agenesis/Dysgenesis - Mullarian Agenesis: Mayer-Rokitansky-Kuster-Hauser syndrome (MRKH). Get agenesis of vagina +/- uterus. Very very very rare for ovaries to be agenic as well in this condition. -AIS (androgen insensitivity syndrome) Secondary - synechia (scarring) of the uterus. Can be due to infection or Asherman's. |
Amenorrhea and Infertility
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General causes of delayed puberty/amenorrhea (broad classifications)?
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Hypothalamus, Pituitary, Thyroid gland, Adrenal Gland, Uterus, Ovaries, Outflow tract abnormalities, Genetic.
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Amenorrhea and Infertility
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If you got a u/s report that said that a young girl didn't have any ovaries, what would be your next step?
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Integrate it with the clinical picture and your knowledge of where the report came from. Often technicians in remote locations aren't used to doing pelivic u/s on young girls, may not be done correctly. Also ovaries could be very small or in different place (eg. in inguinal canal).
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Amenorrhea and Infertility
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What is androgen insensitivity syndrome?
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X-linked recessive. Androgen insensitivity syndrome (AIS) is when a person who is genetically male (XY) is resistant to androgens. As a result, the person has some or all of the physical characteristics of a woman, despite having the genetic makeup of a man. Get male levels of testosterone but don't have the receptors for it to act on.
Signs - Increased height, pale areolae, sparse terminal hair (because no testosterone), blind/shortened vagina, bilateral testes but often in wrong place (eg. can get inguinal hernias - 50%, in 5% the abnormally places testes become malignant, Don't have any Mullerian/Wolffian structures (no uterus or vas deferens) |
Amenorrhea and Infertility
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How do you treat androgen insensitivity syndrome?
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Treatment: gonadectomy (remove testes because can become malignant), estrogen replacement, vaginal dilation
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Amenorrhea and Infertility
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What is Mayer-Rokitansky-Kuster-Hauser (MRKH)? How do you treat?
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Also called Mullerian Agenesis
Get Vaginal Agenesis + Uterine agenesis/ dysgenesis (something there but not what it is suppose to be). (Some women still have a uterus - can still get pregnant if stabbed post oral-sex) • Renal anomalies (30 -40%, ectopic kidneys, unilateral renal agenesis) are really common. Renal and Mullerian systems develop at same time. Skeletal abnormalities also common Remember that ovaries are normal, so having a surrogate carry her child makes pregnancy possible. • Treatment: dilatation with plastic dilators; if fails, surgical vaginoplasty with graft |
Amenorrhea and Infertility
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What is infertility? Difference between primary and secondary?
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Infertility - failure to conceive after one year of regular unprotected intercourse
• primary infertility: no prior pregnancies • secondary infertility: previous conception |
Amenorrhea and Infertility
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How many couples are affected by infertility?
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Affects 10-15% of couples. Remember that 60% of couples achieve pregnancy within 6 months of trying (Remember 60 in 6), 80% within 1 year, and 90% within 2 years.
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Amenorrhea and Infertility
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Broad categories of things we think about with female infertility?
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• ovulatory dysfunction (15-20%)
• tubal factors (20-30%): Pelvic inflammatory disease, tubal ligation • cervical factors (5%): • uterine factors (< 5%): congenital anomalies, intrauterine adhesions (Asherman's syndrome), infection, leiomyomata (benign smooth muscle neoplasm) |
Amenorrhea and Infertility
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Things that can cause male infertility?
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Inadequate or abnormal production of sperm
- congenital (Kleinfelter’s) - physical injury (trauma, heat, radiation) - varicocele (usually left sided due to anatomy; abnormal enlargement of the vein that is in the scrotum draining the testicles. Heats them up) - infection (usually mumps or TB orchitis) - smoking, stress, alcohol, chronic disease or malignancy Sperm delivery problems - bilateral obstruction of epididymis or ducts - ejaculatory dysfunction, e.g. retrograde ejaculation - erectile dysfunction - abnormal position of urethral orifice |
Amenorrhea and Infertility
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What is the first test you do with a potentially infertile male? Things to look for? Secondary tests?
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Semen analysis. Look for
Volume (2-5 ml), count (20 million sperm/mL), motility (> 50%), morphology: > 60% normal forms), TZI - a measure of number of abnormalities (should be < 1.6), pH, WBC (< 10 per high power field). If semen analysis is abnormal, you might test TSH, FSH, Testosterone, Prolactin. |
Amenorrhea and Infertility
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Rank these contraceptive methods in order of effectiveness. (Using the actual, not theoretical efficacy)
Male sterilization, male condom, female sterilization, female condom, IUS, IUD, oral contraceptives, diaphragm/cervical cap/sponge, patch/ring |
Male sterilization 1.5
Intrauterine system (IUS) 1 Female sterilization 5 IUD 8 Injectable contraceptive 30 Oral contraceptives 80 Patch/Ring 80 Male condom 150 Diaphragm/cervical cap/sponge 16-320 Female condom 210 No contraceptives 850 *Numbers refer to pregnancies for every 1000 women during first year of use. |
Contraceptives
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List 6 barrier contraceptives methods
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Female and male condom - should be used with water based lube only
Spermicide Diaphragm Cervical cap Sponge * Diaphragm, cervical cap and sponge all provide some protection against STIs. Need fitting (except for sponge). Use with spermicide and leave in place for 6-8 hr |
Contraceptives
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How do combined oral contraceptives work?
BTF |
Suppress pituitary secretion of FSH and LH. This suppresses LH surge and inhibits ovulation.
Also alter cervical mucous so it is less permeable by sperm) and causes the endrometrium to atrophy partially (results in decreased implantation) |
Contraceptives
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Pros and cons of combined oral contraceptive pills.
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Pros - Menstrual regulation, improved menorrhagia, dysmenorrhea, PMS, endometriosis, decreased ectopic pregnancy, PID. Decreased androgens - acne, hirsutism, decreased benign breast disease.
Cons - Increases coagulation (increased factor II/VII/IX/X/XII/XIII/fibrinogen, decreased protein C). Can get VTE, Stroke, MI. Smoking and hypertension very important risk factors. |
Contraceptives
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Several meds impair the efficacy of OCP. What is the most important one you have to look out for?
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Anticonvulsants have a big effect on how OCP are metabolized.
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Contraceptives
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What is the mechanism of action of the progestin-only pill? (Sometimes also called the mini-pill)
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Mechanisms: Increase/thicken cervical (Cx) mucous, Decrease the amount of endometrium (atrophy, therefore can also cause spotting. This is a big SE) - These are the two big mechanisms.
Inhibits only 60% ovulation cycles. Potentially slows cilia in tubes |
Contraceptives
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Three options for progestin-only contraceptives.
(Progestins are a synthetic progestogens that bind some progesterone receptors in the body, but not all) |
Oral contraceptives (Micronor), Injectable contraceptives (DepoProvera), Intrauterine system (Mirena)
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Contraceptives
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Combined OCP contain estrogen and progesterone. What are the effects of progestrogen excess/deficiency?
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Excess - Increased appetite, depression, fatigue, weight,. Hypertension, dilated veins, hypo-/amenorrhea, cervicitis, moniliasis (yeast infection).
Deficiency - Break through bleeding (d 10-21), dysmenorrhea, menorrhagia, delayed withdraw bleeding, PMS. |
Contraceptives
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Combined OCP contain estrogen and progesterone. What are the effects of estrogen excess/deficiency?
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Excess - (Estrogen excess creates pregnancy like symptoms) = PMS, ectropion (Cervical ectropion (or cervical erosion) is a condition in which the central (endocervical) columnnar epithelium protrudes out through the external os of the cervix and onto the vaginal portion of cervix, undergoes squamous metaplasia, and transforms to stratified squamous epithelium), mucorrhea (excessive production of mucous, often linked to ectropion), cystic breast, dysmenorrhea, menorrhagia, DVT, CVA (Stroke).
Deficiency - Vaginal atropthy, break through bleeding (d1-9/daily), hypo-/amenorrhea. |
Contraceptives
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Almost all of the combined OCP are anti-androgenic. They do vary in their amount of activity though. What are some effects of androgen excess/deficiency?
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Excess- acne, hirsutism, cholestatic jaundice, rash/pruitis, edema, weight gain.
Deficiency - Decreased libido, osteopenia/perosis. |
Contraceptives
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Pros and cons of the progestin only pill?
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Pros - No estrogen so can use in smokers, lactation, migraines, etc. Immediate return to fertility. 10% amenorrhea.
Cons - Potential for break through bleeding, Back-up for 48 hours if miss one pill and must take at same time every day (becasue cervical mucous returns to normal very quickly), can get increase in functional ovarian cysts, and can increase chance of an ectopic pregnancy if pt pregnant. |
Contraceptives
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What is a IUS? How does it work?
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Mirena: IUD containing levonorgestrel (synthetic progesterone derivative)
- Mechanism: Sterile foreign body reaction (SFBR), thins endometrium, increases Cx mucous, may inhibit ovulation |
Contraceptives
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Pros and cons of an IUD
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Pros: lasts 5-8 yrs, cheap ($90-$140)
Cons: insertion (expulsion, perforation, infection, nulliparous women are slightly more likely to expel), Some break through bleeding (but not as bad because no hormones), increased flow/dysmenorrhea (not increased PID) |
Contraceptives
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What is an IUD and how does it work?
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An intrauterine device (Nova-T/Flexi-T) is a T-shaped plastic + copper wire. Not hormonal!
- Mechanism: Sterile foreign body rxn: causes impaired sperm transport + implantation), Fallopian tubal motility, toxic effect on spermatozoa (copper), increases Cx mucous |
Contraceptives
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Pros and cons of DepoProvera?
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Pros: effect within 24 hrs, amenorrhea (50% 1 yr, 80% 3 yrs), decreased seizures, decreased endometrial/ovarian cancer, decreased PID, decreased PMS/endometriosis, may enhance breastfeeding.
Cons: Lots of break through bleeding, weight gain (this is the contraceptive method most closely connected to weight gain), slow return menses (avg. 9 mo, 90% 2 yrs), decreased bone density. |
Contraceptives
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How does DepoProvera work?
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This form of progestin DOES inhibits ovulation through receptors at hypothalamic pituitary level (prevent LH surge); But also increases Cx mucous, decreases endometrium
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Contraceptives
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Pros and Cons of the IUS?
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Pros: lasts 5 yrs, oligo/amenorrhea (40-50 % 1yr), decreased endometriosis, most drug plans cover, return menses 1-3 mos
Cons: must be inserted, Do get some break through bleeding (usually more for first 3 months), costly (no plan = $380) |
Contraceptives
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What is the option for emergency contraception? How does it work?
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Plan B - 750 ug Levonorgestrel, repeat 12 hr. Overall 85% effective. (95% <24 h, 85% 24-48 h, 58% 48-72 h).
Works by modifying endometrium and delaying/ inhibiting ovulation. Available OTH in most provinces (Saskatchewan behind counter; prescription in PQ) |
Contraceptives
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How is a female sterilization preformed?
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Tubal ligation thru Laparotomy (Pomeroy) or Laparoscopy. Can also do a Hysteroscopy which is a tubal occlusion with a coiled wire (Essure or Adiana)
The younger the pt is when procedure is done the more likely it is to fail. Also, procedure itself is covered by MSI but reversal is not so they have to be really sure. Increases risk of ectopic pregnancy because you have blocked tubes. |
Contraceptives
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Important things to remember with male sterilization?
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Office procedure with minimal recovery. Covered by MSI
Need to use a back-up contraceptive method until a semen analysis is done at 3 mo to ensure no sperm sneaking through. |
Contraceptives
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What are the steps involved in the fertilization of an egg by a sperm - usually occurs in ampulla of Fallopian tube.
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Ejaculation and sperm is in female reproductive tract.
1. Sperm activation - 'capitation' - remove proteins causing a head that is better able to adhere to an egg and increased mobility. 2. Chemoattraction of the sperm to the ovum by substances produced by the ovum. 3. Adherence to the zona pellucida, (pell-ooo-ca-da) the membranous structure surrounding the ovum 4. Penetration of the zona pellucida and the acrosome reaction. Sperms bind to a sperm receptor in the zona pellucida, and this is followed by the acrosomal reaction (breakdown of the acrosome, releasing enzymes which help break down the the zona pellucida). In order to fertilize egg sperm needs to cross (in order): cell membrane, corona radiata, and zona pellucida. |
Intro to Embryology
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How is the pelvis oriented in the anatomical position?
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Downward slanted, with the upper margin of the pubic symphysis and anterior superior iliac spines lying in the same vertical planes
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Pelvic Anatomy
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What is the sacral promontory?
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On the inside of the pelvis. A anterior projection on the upper anterior margin of the first sacral vertebrae (S1). Forms the posterior boundary of the pelvic inlet.
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Pelvic Anatomy
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What are the four small holes on each side of the anterior and posterior surface of the sacrum?
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Anterior sacral foramina allow the passage of ventral rami of sacral nerves. The posterior sacral foramina allow dorsal rami to pass.
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Pelvic Anatomy
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What is the ischial spine? What is above and below it? What ligament attaches to it?
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Posterior border of the ischium projects medially and backward to form the small finger sized projection of the ischial spine. The sacrospinous ligament attaches to the ischial spine and separates the greater (above) and lesser sciatic notch.
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Pelvic Anatomy
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What forms the pelvic brim (pelvic inlet)? What two parts of the pelvis does this separate?
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From anterior (pubis symphysis) to posterior - pubic crest, pectineal line (pecten pubis), arcuate line, ala of sacrum, sacral promontory. Above this brim is the greater (false pelvis). Below it is the lesser (true) pelvis.
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Pelvic Anatomy
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What is the pelvic outlet?
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The bottom circle that the lesser pelvis makes. The circle you would see if you looked at it from bottom up.
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Pelvic Anatomy
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What is the diagonal conjugate (pelvic conjugate) diameter?
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The distance between the lower margin of the pubic symphysis and the sacral promontory. The only distance that can be measure per vaginum.
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Pelvic Anatomy
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What are your 'sit bones'?
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Ischial tuberosity or the tuberosity of the ischium.
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Pelvic Anatomy
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What is the pubis symphysis?
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A fibrocartilagenous joint that connects the right and left pubis.
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Pelvic Anatomy
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How is the sacrum attached to the hip bone?
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The sacroiliac joint is supported by a number of ligaments, including the posterior and anterior sacroiliac ligaments.
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Pelvic Anatomy
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Where do the sacrotuberous and the sacrospinous ligament attach to and from?
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Sacrotuberous ligament - posterior surface of the sacrum to the ischial tuberosity. Sacrospinous ligament (anterior to the sacrotuberous ligament) runs from the posterior surface of the sacrum to the ischial spine.
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Pelvic Anatomy
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What are the peritoneal reflections in males and females?
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Men: The rectovesicular pouch.
Women: The vesicouterine pouch and the rectouterine pouch (pouch of Douglas). 'Vesico' = bladder |
Pelvic Anatomy
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How is the uterus oriented relative to the vagina?
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The uterus is usually antevered (tipped anteriorly relative to the axis of the vagina) and anteflexed (uterine body is flexed or bent anteriorly over the cervix so its mass lies tilted over the bladder). in 10% of women the uterus can be found bending and tilting backwards, then it is considered to be retroverted and in a retroflexed position.
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Pelvic Anatomy
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What are the retroperitoneal organs?
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Think SAD PUCKER:
S = Suprarenal glands (aka the adrenal glands) A = Aorta/IVC D = Duodenum (second and third segments [some also include the fourth segment] ) P = Pancreas (tail is intraperitoneal) U = Ureters C = Colon (only the ascending and descending colons, as transverse and sigmoid retain mesocolon) K = Kidneys E = Esophagus R = Rectum |
Pelvic Anatomy
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What is the broad ligament of the uterus?
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A sheet like fold of peritoneum that runs form the lateral pelvic wall to the uterus. Encloses uterine tubes in its superior margin and suspends the ovary from its posterior aspect.
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Pelvic Anatomy
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What is the part of the broad ligament over the uterine tubes called? What is the part attached to the ovary called?
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Mesosalpinx - the part of the broad ligament over the uterine tubes. The mesovarium is the part attached to the ovary. (It is through the mesovarium and the suspensory ligament that the ovarian veins and arteries enter the ovary.
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Pelvic Anatomy
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What is contained in the free edge of the broad ligament?
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The medial 4/5th of the superior free age of the broad ligament contains the uterine (Fallopian) tube. The lateral 1/5 is occupied by ovarian vessels that enter the pelvis from the posterior abdominal wall in a porion of the broad ligament known as the suspensory ligament of the ovary.
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Pelvic Anatomy
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What does the levator ani attach from?
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The tendinous arc is a thickening of the obturator membrane, the fascia covering the obturator internus muscle. Levator ani muscles attach to this.
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Pelvic Anatomy
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What muscles is the pelvic floor/diaphragm made up of?
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The Puborectalis muscle (small band anterior to pubococcygeus muscle), The two levator ani muscles -pubococcygeus (anterior half of the levator ani) and iliococcygeus (posterior 1/2) and the two coccygeus (the ischiococygeus) muscle (posterior part of the pelvis).
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Pelvic Anatomy
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What is the piriformis muscle?
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A muscle that come from the sacrum and attaches to the greater trochanter. Important in movement of the lower limb. Piriformis arises from 3 points of attachment - at bone bridges between the 2nd, 3rd, and 4th anterior sacral foramina. Passes out of pelvis through the greater sciatic foramen.
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Pelvic Anatomy
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What is the obturator internus?
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A deep internal rotator of the lower limb. It is a fan shaped muscle that originates from the deep surface of the obturator membrane and from associated regions of the pelvic bone that surronds the obturator foramen. Passes through the lesser sciatic foramen.
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Pelvis Anatomy
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What does the pelvic floor do?
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Supports the pelvic viscera and raises the pelvic floor. Some of the central muscle fibers of the more medial muscle reinforces the external anal sphincter, and in women functions as a vaginal sphincter. Resists increased internal pressure during forced expiration and defecation.
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Pelvic Anatomy
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What is the triangular space at the base of the bladder called?
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The urinary trigone is a smooth tringular space at the base of the bladder on the posterior side. Paired opening for the ureters and a single opening for the urethra at the base.
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Pelvic Anatomy
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What is the ampulla of the vas deferens?
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The dilated distal portion of the vas deferens as it joins the seminal vesicles on the posterior superior border of the prostate.
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Pelvic Anatomy
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What are the different portions of the urethra and where is each located?
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The urethra comes off the trigone of the bladder (bladder neck) and passes into the prostate as the prostatic urethra. Between the prostate and the bulb of the penis it passes through the perineal membrane as the Membranous Urethra. Finally it enters the bulb of the penis and travels through the corpus spongiosum as the Spongy or Penile Urethra.
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Pelvic Anatomy
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Where are the seminal vesicles?
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Located behind and below the urinary bladder.
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Pelvic Anatomy
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What are the ejaculatory ducts?
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Each ejaculatory duct is formed by the union of the vas deferens with the duct of the seminal vesicle. Passes through the top-back of the prostate to open in to the prostatic urethra.
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Pelvic Anatomy
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What makes up the body of the penis?
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Free cylindrical part called the body, which is formed of three elongated columns of erectile vascular tissue - two corpus cavernosa and one corpus spongiosum. The corpus cavernosa are surrounded by deep fibrous tissue that forms an incomplete septum between each corpus.
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Pelvic Anatomy
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What runs down the centre of each corpus of the penis?
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A deep artery of the penis (branch of the internal pudendal artery) runs down the centre of each corpus cavernosa, and the penile urethra runs down the corpus spongiosum.
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Pelvic Anatomy
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What is the name for the head of the penis and the foreskin? Origin of the head?
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The Glans penis is the head. It is an extended part of the corpus spongiosum that fits like a cap over the terminal part of the corpora cavernosa. The foreskin is called the prepuce, and it is the double fold of skin at the junction of the glans and body of the penis.
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Pelvic Anatomy
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What are the crura of the penis? What is their function? What are they covered by?
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The left and right crura are the proximal ends of the corpus cavernosa. They project back in to the pelvis and are attached to bone (ischiopubic rami). Allows them to anchor and support penis during erection. They are also the main erectile element of the penis. Each one is covered on its superficial surface by the ischiocavernosus muscle.
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Pelvic Anatomy
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What is the bulb of the penis? Where is it attached to? What muscle covers it?
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Continuous with the corpus spongiosum. Attached posteriorly to the midline of the perineal membrane. Covering the bulb of the penis is the Bulbospongiosum muscle.
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Pelvic Anatomy
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What is the perineal membrane? What is another name for it? Where is it?
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The perineal membrane or the interior fascia of the urogenital diaphragm is the wedge shaped space between the crura and the bulb of the pensi.
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Pelvic Anatomy
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Trace the descending aorta until it starts supplying individual structures
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Beneath the peritoneum, the descending aorta bifurcates into the common iliac arteries. Then each divides into external and internal iliac arteries at the level of the pelvic brim. The external iliac exits pretty quickly as the femoral artery, while the internal iliac supplies most of the structures of the pelvis. Branches into two main divisions - the anterior and posterior divisions. Posterior division has three somatic branches and anterior division has three somatic and four visceral.
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Pelvic Anatomy
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What is the most important artery that comes from the posterior division of the internal iliac artery?
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The superior gluteal artery is the largest branch of the internal iliac artery. Exits through the greater sciatic foramen superior to the piriformis muscle and the SI spinal nerve root. Supplies the gluteal region.
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Pelvic Anatomy
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What are the three important somatic branches of the anterior division of the internal iliac artery?
*remember that these branches are very variable and should be identified by the structure they supply and not by their branching pattern. |
1. Inferior gluteal artery - Generally exits the pelvic cavity below S1 spinal nerve root. Leaves the pelvis with the piriformis muscle through the greater sciatic foramen to enter the gluteal region.
2. Internal pudendal artery - Supplies the external genitalia. May arise as a branch of the inferior gluteal artery or as a separate branch off the internal iliac. Smaller than you expect and hard to see. Best way to identify it is to look for its path. Exits below piriformis from greater sciatic formen with the pudendal nerve and then they re-enters through lesser sciatic formen. 3. Obturator Artery - runs along pelvic wall as it exits the pelvic cavity through the obturator foramen along with the opturator nerve and vein. |
Pelvic Anatomy
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What are the three most important visceral branches of the anterior division of the internal iliac artery?
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The superior and inferior vesicle arteries which supply the superior and inferior part of the bladder.
The uterine artery - Runs along the base of the broad ligament to the cervix. Along its course it crosses the ureter. Anastomoses with the ovarian artery. The uterine artery is the major blood supply to the uterus and enlarges significantly during pregnancy. |
Pelvic Anatomy
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Outline briefly the divisions of the nervous system.
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Nervous system can be divided into: Peripheral and Central nervous system
The peripheral nervous system can be divided into: Sensory (Sends info to CNS from internal organs or external stimuli) and Motor nervous system (carries info from CNS to organs, muscles and glands). The motor nervous system can further be divided into: Somatic nervous system (voluntary) and the autonomic nervous system (involuntary). Finally, the autonomic nervous system can be divided into: Paraympathetic (Rest/Digest) and Sympathetic (Fight/Flight) divisions. |
Pelvic Anatomy
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What are the two major groups of autonomic (involuntary) nerves in the pelvis?
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Formed by 1. sympathetic nerves (coming from the sympathetic chain) and 2. parasympathetic nerves (the pelvic splanchnic nerves from the ventral rami of S2-S4 segment of spinal cord). Together these two sets of nerves form an autonomic plexus on each side of the rectum.
Looks like a bunch of membranous/ fatty threads. |
Pelvic Anatomy
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What are the main somatic (voluntary) nerves in the pelvis? What major nerve originates from this plexus?
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These nerves supply the muscles, skin and joints of the pelvis and perineum. Make up the lumbo-sacral plexus. Consists of the ventral rami of L4. L5 and S1-S4 both lying over piriformis muscle on the anterior surface of the sacrum. The pudendal nerve originates from this plexus.
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Pelvic Anatomy
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What is the course of the pudendal nerve?
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Originates from the ventral primary rami of S2-S4. Exits through the greater sciatic foramen to gluteal region, and then leaves the gluteal region through the lesser sciatic formen to enter the pudendal canal in the perineum.
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Pelvic Anatomy
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What are the three important branches of the pudendal nerve in the male?
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1. Inferior rectal (haemorrhoidal) nerve - innervates the anal sphincter and the perianal region
2. Perineal nerve - the chief nerve supply to the urogenital region except for the skin of the penis. 3. Dorsal nerve of the penis - leaves the pudendal canal and passes through the pubic arch. Curves forward with the artery between the corpus cavernosum and the pubic bone and appears at the dorsal surface of the penis in males. |
Pelvic Anatomy
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What are the three major nerves that supply the male perineum?
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1. Pudendal nerve.
2. Ilioinguinal nerve - Sensory. Runs in the inguinal region. Gives anterior scrotal branches that supplies skin of the scrotum 3. Genitofemoral nerve. Motor and sensory. Supplies the cremaster muscle with motor branches and sensory branches to the skin of the thigh. |
Pelvic Anatomy
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What are the structures that a sperm passes on its route from the testes to exit from the spongy urethra?
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Sperm is stored in the epididymis. After its release it travels in the vas deferens to enter the abdominal cavity through the deep inguinal ring. It then reaches the prostate in the pelvic cavity. In the prostate it is mixed with fluid from the seminal vesicle and the prostate. It then travels through the prostatic urethra, membranous urethra, and lastly the spongy urethra.
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Pelvic Anatomy
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What does the bulbospongiosus muscle do?
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Empties the urine/semen at the end of micturition/ejaculation in the male. In the female it acts as a sphincter for the vagina.
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Pelvic Anatomy
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Name the part of the Fallopian tube as you move down from the part touching the uterus.
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Interstitial part (the part that still is the uterus), Isthmus, Ampulla, Infundibulum (slopes down towards the fimbriae), Fimbriae
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Pelvic Anatomy
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Where are the fundus of the uterus and the internal and external os?
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The fundus of the uterus is the very top of the uterus where implantation will ideally occur.
The internal and external os of the cervix are the upper (internal is internal relative to the uterus) and lower border (the part of the cervix that is more external) of the cervix. The external os can be visualized on speculum exam. |
Pelvic Anatomy
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The uterus is anchored by three ligaments, formed by condensation of pelvic fascia. What are these ligaments and where do they attach?
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1. Lateral (Cardinal) Ligaments - From the cervix to the lateral wall of the pelvis.
2. Pubocervical ligaments - From the cervix to the pubic symphysis. 3. Uterosacral ligaments - From the uterus to the sacrum. *These ligaments are difficult to find in the cadaver. |
Pelvic Anatomy
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What are the vaginal fornices? What is their clinical significance?
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The deepest portions of the vagina, extending into the recesses created by the vaginal portion of cervix. There is an anterior and posterior fornix. The posterior fornix lies next to the pouch of Douglas, which means that this area can be palpated (eg. when suspecting pus or blood within the peritoneal cavity) through the posterior vaginal fornix.
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Pelvic Anatomy
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The female external genitalia are homologous structures to those of the male. The differences are due to sexual differentiation and are expressed in terms of the size and the absence of midline fusion of some of the elements. Two other differences?
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1. Major reduction in the size of the erectile elements in female relative to the male.
2. The labium majorum and minorum are more adherent to the underlying contents of the superficial perineal pouch, |
Pelvic Anatomy
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What is the function of the round ligament of the uterus? Attachment?
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Helps support the position of the uterus. Extends from the uterus to the anterior abdominal wall at the deep inguinal ring and then descends into each labium majorum.
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Pelvic Anatomy
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What is the position of the ischiocavernosus and bulbospongiosus muscle in the female?
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The ischiocavernosus muscle (dark coloured at base of labia majorum) covers the unattached surface of the crus of the clitoris on each side.
The bulbospongiosus muscle surronds the vaginal orifice like a sphincter. Posteriorly it is attached to the perineal body. |
Pelvic Anatomy
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What is the female homologue to the bulb of the penis? Where is it? Major difference from the male bulb?
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The Bulb of the Vestibule - elongated massses of erectile tissue on each side of the vestible of the vagina. Main difference from bulb of the penis is that in female these structures are paired.
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Pelvic Anatomy
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What are the Greater Vestibular Glands in the female? What happens if these get inflamed?
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Aka. Bartholin's Glands. Situated at the posterior blunt end of the bulb of the vestibule; the ducts open into the vestibule. Secrete some lubrication. An inflammation or abscess of these glands produces a swellingin the posterior half of the labium known as Bartholin's Cyst.
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Pelvic Anatomy
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What is the vestibule of the vulva?
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The Vulval vestibule is a part of the vulva between the labia minora into which the urethral opening and the vaginal opening open.
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Pelvic Anatomy
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What is the perineal body? What is the main difference in structure and function in the perineal body in males and females?
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The perineal body is a fibromuscular area that runs between the the urogenital triangle and the anal triangle. It gives attachment to superficial and deep perineal muscles. If this is injured suport to the pelvic floor is lost. In males - between bulb of penis and anus. In females between vagina and anus. It is much larger in females than males.
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Pelvic Anatomy
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What vessel supplies the uterus? Follow its path to the uterus.
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The uterine artery usually arises directly from the internal iliac artery. Travels to the base of the uterus, where it gives cervical and vaginal branches before it anastomoses with the ovarian artery.
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Pelvic Anatomy
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What is the relationship between the uterine artery and the ureters? Why is this clinically important?
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The uterine artery crosses in front and superior to the ureter (Water under the bridge) as it comes off the pelvic wall. The close relation of ureter to the uterine artery as it passes below the uterine artery commonly leads to damage to the ureter during surgery in the female pelvis.
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Pelvic Anatomy
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When would you do a Pudendal Block? How?
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Pudendal block anaesthesia is performed to relieve the pain associated with childbirth. The injection is usually given where the pudendal nerve crosses the lateral aspect of the sacrospinous ligament near its attachment to the ischial spine. During childbirth, a finger inserted into the vagina can palpate the ischial spine. The needle is passed transcutaneously to the medial aspect of the ischial spine and around the sacrospinous ligament. Infiltration is performed and the perineum is anesthetized.
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Pelvic Anatomy
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What are the three main branches of the pudendal nerve in the female?
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This is the order they branch in as the nerve moves from back to front.
1. Inferior rectal (hemorrhoidal) nerve 2. The R and L perineal nerves. These are the chief nerve supply to the urogenital region, except for the skin of the penis or the clitoris. It divides into two main branches in the pudendal canal: a) Sensory branch - Superficial (Posterior) Labial Branches. Supply the skin of labia majora. b) Motor branch - Deep Branches - supply the perineal muscles in the urogenital triangle. 3. Dorsal nerve of the clitoris - Leaves the pudendal canal, passes forward through the urogenital diaphragm to reach the pubic arch. Curves forward with the artery between the corpus cavernoum and the pubic bone and appears at the dorsal surface of the clitoris. |
Pelvic Anatomy
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What four nerves supply the female perineum?
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1. Pudendal Nerve (and its three branches).
2. Ilioguinal Nerve - sensory - Runs from the inguinal ring and supplies the skin of the laial majora. 3. Genitofemoral nerve - motor and sensory. Can see this in the psoas muscle in the pelvis. Its genital and femoral branches may not be visible. 4.Pelvic autonomic plexuses |
Pelvic Anatomy
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What is the pudendal canal? What are its contents?
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It is a tubular compartment formed in the fascia that covers the obturator internus muscle which these vessels/nerves pass thru after re-entering the pelvis through the lesser sciatic foramen. The pudendal canal contains the pudendal nerve, internal pudendal artery and vein.
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Pelvic Anatomy
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What supports the uterus?
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The uterus is mainly supported by the tone of the levator ani muscle and the condensation of pelvic fascia, known as ligaments.
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Pelvic Anatomy
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If a woman has a longer menstrual cycle (eg. 35 days instead of 28) how does that change her EDC (Estimated date of confinement)?
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For a longer menstrual cycle you add on days to the EDC so it is later, because presumably fertilization no longer occurs 14 days after the first day of menstruation.
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Obs/Gyn Lab Session
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How is symphysis-fundal height measured? What is normal at 12 weeks? 20 weeks? >20 weeks?
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Measured - Distance over the abdominal wall from the top of the symphysis pubis to the top of the fundus measured in cms. Would expect:
12 wks – at symphysis pubis, 20 wks – at umbilicus, > 20 wks – gestational age ± 2 cm |
Obs/Gyn Lab Session
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What are some reasons for a smaller symphysis-fundal height than expected? Larger?
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Small - Wrong dates, Small for gestational age / growth restricted fetus (IUGR), Oligohydramnios (insufficent volume of amniotic fluid), Fetus in transverse lie.
Big - Wrong dates, Molar pregnancy, Multiple gestation, Large for gestational age fetus, Polyhydramnios, Maternal obesity, Maternal fibroid uterus. |
Obs/Gyn Lab Session
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List the four Leopold Maneuvers?
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1. Identification of fetal pole at uterine fundus – breech (large, nodular) vs. head (hard, round, mobile)
2. Palms are placed on either side of the maternal abdomen to determine fetal back (firm, resistant) vs. fetal parts (small, irregular, mobile) 3. Use thumb & fingers to grasp presenting part just above symphysis pubis. Usually do this one first. 4. Examiner faces mother’s feet and with the tips of the first 3 fingers of each hand exerts pressure in the direction of the axis of the pelvic inlet to determine position of presenting part. This is rarely done. |
Obs/Gyn Lab Session
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What is the purpose of the Leopold Maneuvers?
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Used to determine fetal lie, presentation & position
1. Lie – relationship of the long axis of the fetus to that of the mother. Can be longitudinal or Transverse. 2. Presentation – presenting part. Can be Cephalic – fetal head (vertex, face or brow) or Breech – buttocks (frank or complete) or footling 3. Position – relationship of the presenting part to the maternal birth canal. |
Obs/Gyn Lab Session
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What are the four different types of female pelvis shapes? What fetal presentation are they associated with?
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1. Gynaecoid (50%) - slightly transverse oval inlet, wide sacrum, straight side walls with blunt ischial spines. Best prognosis for vaginal delivery (cephalic presentation & OA position)
2. Anthropoid (25%) - Elongated in AP diameter. Associated with OP position 3. Android (20%) - Heart shaped. Like a boy. Worst prognosis for vaginal delivery (malpresentation) 4. Platypelloid (5%) - Shortened AP diameter. Associated with face presentation & OT position. *This is not really determined any way other than giving birth and seeing how vaginal delivery goes and the way the baby presents. |
Obs/Gyn Anatomy Lab
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How is pelvic size clinically estimated? (3 strategies)
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Pelvic Inlet Estimation
1. Diagonal conjugate - Distance from the sacral promontory to the lower margin of the symphysis pubis. Estimate of the AP diameter of the pelvic inlet. 2. Obstetrical conjugate - Shortest AP diameter through which the fetal head must pass in descending through the pelvic inlet. Distance from the sacral promontory to the upper margin of the symphysis pubis 3. Pelvic Outlet Estimation - Bi-ischial diameter / Intertuberous diameter. Diameter between the ischial tuberosities. |
Obs/Gyn Anatomy Lab
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Describe the normal fetal heart rate and rhythm
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Normal baseline – 110-160 bpm. Normal rhythm – regular with variability and accelerations (with fetal movement). If irregular – may represent a fetal arrhythmia requiring further investigation.
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Obs/Gyn Anatomy Lab
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What does it mean for the vertex to be engaged during labor?
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Means that the widest part of the presenting part has gone through pelvic inlet. In a normal birth that means the PBD - Biparietal Diameter of the head is resting at ischial spines.
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Obs/Gyn Anatomy Lab
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What is station in labor?
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The relationship of the presenting part to an imaginary line drawn between the ischial spines.
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Obs/Gyn Anatomy Lab
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What are the 5 components of a Bishop Score and what do they mean?
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1. Station
2. Dilation - Measure of the diameter of the stretched out cervix (cm). 3. Effacement - Measure out of the thinning out of the cervix. As stretched out gets thinner. When fully thinned out - like paper (% value). 4. Consistency - How tough (and therefore resistant to stretching) the cervix is. (Firm - nose, intermediate - cheek, soft - lips) 5. Position - Of the cervix itself (Ant - pointing towards bladder, intermediate, or posterior) |
Obs/Gyn Anatomy Lab
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What does a Bishops score tell you?
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Assesses cervix for readiness for labor or how baby is making progress during delivery. Score of <6 indicates labor is unlikely to start without induction, but a low score also means that induction is less likely to be successful.
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Obs/Gyn Anatomy Lab
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What are the 5 bones in a baby's head?
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From back, clockwise - Occipital bone. Parietal bone, Frontal bone, Frontal bone, Parietal bone.
(Should be able to draw all of these out) |
Obs/Gyn Anatomy Lab
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What are the four sutures (lines) in a baby's head and where are they located?
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1. Lamboidal Suture - between the occipital bones and the two parietal bones.
2. Saggital Suture - Between the two parietal bones. 3. Coronal suture - Between the frontal and parietal bone 4. Frontal suture - Between the two frontal bones. |
Obs/Gyn Anatomy Lab
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What are the two fontanelle (soft spot) regions in a baby's head?
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1. Posterior fontanelle (triangular shaped area between the occipital bone and the two parietal bones.)
2. Anterior fontanelle (Bregma) - Diamond shaped area formed where the two frontal and the two parietal bones all meet. |
Obs/Gyn Anatomy Lab
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What is the position of the fetal head expressed in relation to?
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The relation of the fetal occiput to the maternal pelvis. (Eg. Occiput anterior mans baby's occiput is pointing towards the anterior of mother.)
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Obs/Gyn Anatomy Lab
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At term, what is the most common position of the fetal head as it enters the maternal pelvis? What about when patient is pushing in the second stage of labor - what position then is most likely to result in a spontaneous vaginal delivery?
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As it enters pelvic inlet - Transverse. This is the way it fits best.
At delivery - Occiput anterior. |
Obs/Gyn Anatomy Lab
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What are the cardinal movements of labor?
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Engagement
Don't - Descent Forget - Flexion (tucks head, smallest diameter) I - Internal Rotation (to OA) Enjoy - Extension (head back) Expensive - External Rotation (rotates head back in line with body) Equipment - Expulsion |
Obs/Gyn Anatomy Lab
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What is Spermatogenesis?
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Spermatogenesis is when a primary spermatocyte goes through meiosis (requiring DNA synthesis and two meiotic divisions) to produce 4 haploid spermatids (primary and secondary spermatocytes). Can be 23X or 23Y.
Each primary spermatocyte divides into two secondary spermatocytes, and each secondary spermatocyte into two spermatids (immature spermatozoa) |
Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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What is spermiogenesis?
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Spermiogenesis is defined by the development and differentiation of the spermatid head and tail. It is the final stage in the development of sperm, where spermatids (* remember spermatids won't have a tail) transform into mature, motile spermatozoa.
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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What is spermiation?
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Spermiation is the release of mature spermatozoa into the seminiferous tubule lumen. Before this the remaining unnecessary cytoplasm and organelles are removed. The resulting spermatozoa are now mature but lack motility. They are transported to the epidydymis where they gain motility.
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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What is the blood testis border?
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This is one of the most important roles of Sertoli cells in the organization of spermatogenic epithelium. Creates a microenvironment where meiosis and postmitotic development can occur.
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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Briefly describe how the testes form during development and what changes occur during the early postnatal period.
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1. Primordial germ cells migrate to the undifferentiated gonad, at which point it matures into a testes.
2. Primordial germ cells are enclosed in testicular tubules along with the precursor (immature) Sertoli cells. There are undifferntiated spermatogonia which can proliferate mitotically long term. This is the case in newborns. 3. During early postnatal development - mitotic activity slows down followed by a complete and permanent mitotic silencing. 4. This occurs until puberty (I think) when cells start making sperm. |
Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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What hormones regulate spermatogenesis?
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1. FSH and LH secretion and action.
a. LH elevates intratesticular testosterone concentrations 65x higher than systemic concentrations, which is necessary to maintain spermatogenesis. b. Sertoli cells express FSH inducible aromatase, permitting intratubular synthesis of Estrogen. c. Testosterone and FSH act on Sertoli cells in a synergistic way during development. Stimulates Sertoli cells to become mature and fully active cells supporting spermatogenesis and able to respond to interactive signals from the developing germ cells |
Physiology: Gonads, Gametogenesis, Ovulation, and Fertilization
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What happens to the GnRH-LH-T axis in aging males (>60)?
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Get multiple multi-site alterations. Produces hypoandrogenism in aging male. Can get physiological changes (eg. decreased erections) but sperm production continues pretty much unchecked.
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Physiology: Gonads, Gametogenesis, Ovulation, and Fertilization
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Describe the stages of oogenesis (development of oocytes) up until childhood.
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1. Unlike the fetal testis, the fetal ovary begins germ cell development (oogenesis) early in fetal life. During early intrauterine development (15 weeks), primordial germ cells (oogonia) proliferate and migrate.
2. Upon their arrival in the fetal ovary, some of the oogonia continue mitotic proliferation and some begin to undergo apoptosis. 3. Some of these oogonia begin (but do not complete) meiosis and become oocytes. These cells have 2 X chromosomes. By 6 months postpartum, all oogonia have been converted to oocytes. |
Physiology: Gonads, Gametogenesis, Ovulation, and Fertilization
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Describe the stages of oogenesis (development of oocytes) from birth until childhood.
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1. At or near birth, the meiotic process is arrested at prophase of the first meiotic division. The oocytes remain arrested in the diplotene stage of the first meiotic prophase until they are recruited to grow and mature to produce an ovum or they undergo apoptosis.
5. During the first days of postnatal life, the oocytes recruit somatic follicular cells, which are organized into a finite number of "resting" primordial follicles. Primordial follicles are composed of an outer layer of granulosa cells and a small oocyte, both enveloped in a basal lamina. The pool of primordial follicles in the female ovary reaches its maximum number at about 20 weeks of gestational age and then decreases in a logarithmic fashion throughout life until complete depletion occurs during menopause. |
Physiology: Gonads, Gametogenesis, Ovulation, and Fertilization
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Describe the stages of oogenesis (development of oocytes) from childhood until maturity.
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1. Beginning in puberty and extending through the reproductive years, several primordial follicles mature each month into primary follicles. One or two secondary follicles progress to a tertiary or graafian follicle stage. At this stage, the first meiotic division occurs to produce a haploid secondary oocyte and a polar body. During this process, cytoplasm is conserved by the secondary oocyte, and consequently the polar body is disproportionately small. The secondary oocyte halts meiosis at its second metaphase.
2. One of the secondary oocytes is released at ovulation. If the oocyte is fertilized, then completion of the second meiotic division follows. If fertilization fails to occur, then the oocyte degenerates prior to completion of the second meiotic division. (Sperm and secondary oocyte is the ovum. Each month you create a secondary ovuum and a polar body) |
Physiology: Gonads, Gametogenesis, Ovulation, and Fertilization
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The ability to complete meiotic maturation and undergo successful post fertilization development depends on what parameter of the oocyte?
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Oocyte growth - Meiotic competence is acquired during growth. "Depends on what you can pack into your backpack". Just because an oocyte develops doesn't mean it is of good quality.
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Physiology: Gonads, Gametogenesis, Ovulation, and Fertilization
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What organelles are there in developing oocytes?
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1. Increased numbers of mitochondria. (sole source of mitochondrial DNA in the embryo since mitochondria in sperm degenerate).
2. Enlarged golgi body 3.Cortical Granules - Membrane bound vesicles. 4. Centrioles - Centrioles in the oocyte disappear and have to be inherited from fertilizing sperm |
Physiology: Gonads, Gametogenesis, Ovulation, and Fertilization
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How are the seminiferous tubules organized? What three cell types do you find inside and what are their function?
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Inside the testes are the seminiferous tubules. These tubules epithelium is made from Sertoli cells (support and nurturing cells for the sperm). Surrounding the seminiferous tubules are interstitial cells, which include the Leydig cells (primary role is to produce testosterone, which is essential for spermatogenesis.) The tubules are lined with spermatogonium, which will eventually divide to become sperm cells. Along the course of normal seminiferous tubules, one finds sperm present at various stages of development, from the immature spermatogonium to the mature spermatozoon.
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Case 1 - Amenorrhea
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How does fertilization occur? Review the discrete steps in the process.
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1. Capacitation Reaction - Occurs after ejaculation, when sperm has been in female reproductive tract for several hours.Remove some proteins from sperm, destabilizing sperm head membrane and causing hypermotility.
Fertilization usually occurs within the ampulla. 2. Chemoattraction of the sperm to the ovum by substances produced by the ovum. 3. Adherence to the zona pellucida, (pell-ooo-ca-da) the membranous structure surrounding the ovum 4. Penetration of the zona pellucida and the acrosome reaction (breakdown of the acrosome, the lysosome-like organelle on the head of the sperm . Various enzymes are released, including the trypsin-like protease acrosin. Acrosin facilitates but is not required for the penetration of the sperm through the zona pellucida). 5. Adherence of the sperm head to the cell membrane of the ovum, with breakdown of the area of fusion and release of the sperm nucleus into the cytoplasm of the ovum. The fusion provides the signal that initiates development. In addition, the fusion sets off a reduction in the membrane potential of the ovum that prevents polyspermy, the fertilization of the ovum by more than one sperm. |
Case 1 - Amenorrhea
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When should intercourse occur in order to increase the likelihood of fertilization?
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Usually sperm only viable for 48 hours, oocyte for 24 hours. So in order to get pregnant should have sex sometime in-between two days before ovulation to one day after.
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Case 1 - Amenorrhea
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How are GnRH, FSH, LH, estrogen and progesterone hormones involved in ovulation?
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The hypothalamus produces pulsatile secretions of GnRH. This stimulates the anterior pituitary to produce increasing levels of FSH and LH. The FSH stimulates the ovaries to begin recruitment of follicles. The follicles that were being recruited produce estrogen which feeds back to the pituitary. Later, as the follicle-stimulating hormone level decreases, only one follicle continues to develop. Get a LH surge, which causes ovulation. After ovulation, the corpus luteum produces progesterone.
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Case 1 - Amenorrhea
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What happens to hormone levels after ovulation and how does this cause menstruation?
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Progesterone and estrogen cause the lining of the uterus to thicken more, to prepare for possible fertilization. If the egg is not fertilized, the corpus luteum degenerates and no longer produces progesterone, the estrogen level decreases, the top layers of the lining break down and are shed, and a new menstrual cycle begins.
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Case 1 - Amenorrhea
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What are the phases of the menstrual cycle? What happens in each?
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1. Follicular Phase: This phase begins on the first day of menstrual bleeding (day 1). But the main event in this phase is the development of follicles in the ovaries.
2. Ovulatory Phase: This phase begins when the level of luteinizing hormone surges. Luteinizing hormone stimulates the dominant follicle to bulge from the surface of the ovary and finally rupture, releasing the egg. 3. Luteal (Secretatory) Phase: This phase begins after ovulation. It lasts about 14 days (unless fertilization occurs) and ends just before a menstrual period. In this phase, the ruptured follicle closes after releasing the egg and forms a structure called a corpus luteum, which produces increasing quantities of progesterone. |
Case 1 - Amenorrhea
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At which point are the testes and ovary sexually dimorphic? What are primordial germ cells called when they reach the gonad in males and in females?
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Humans are not sexually dimorphic and human gonads are sexually indifferent until approximately 6 weeks of age.
Primordial germ cells are the stem cells that give rise to the oogonia and spermatogonia. |
Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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Mammalian oocytes are uniform (without cellular polarity) until when?
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Until the polar body is extruded. Cell fate and body axis are determined by cellular interactions instead of being predetermined by molecular organization in the egg.
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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When does gene transcription resume after fertilization?
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Not until after the four cell stage. There is a period of several days before and after ferlilization when the cell is entirely dependent on maternal proteins and on translation of mRNA's stored during oogenesis. During this shutdown of transcription the chromatin around the nucleolus condenses.
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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The uterus responds to androgens. How does this become important in PCOS?
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Androgen receptor expression is elevated in women with PCOS and this may explain implantation defects and early pregnancy loss in this syndrome.
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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What is the function of the Fallopian tubes?
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Facilitate gamete and early embryo transport (using tubal epithelium and smooth muscle), locations of fertilization, and nourish the gametes and zygote with tubular fluid. Fimbriae beating at ovulation allows for uptake of the oocyte into tube ampulla.
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization
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How does progesterone change the endometrium in the luteal phase?
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Progesterone causes endometrium to become converted to secretory - thick, spongy well vascularized tissue with special spinal arteries. It also causes it to produce cytokines, growth factors, and specialized cell adhesion molecules, which help create a favorable environment for embryo implantation and survival.
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization.
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When is the endometrium susceptible to implantation of the embryo?
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The endometrium is normally a non-receptive environment for an embryo, except during implantation window. Implantation window is a period during which the endometrium is optimally receptive to implanting blastocyst. Implantation of the human embryo may occur only during a regulated "implantation window" on days 20-24 of the menstrual cycle) (days 6-10 postovulation)
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Physiology: Gonads, Gametogenesis, Ovulation and Fertilization.
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What stage is the oocyte in when it is arrested in Meiosis 1 and Meiosis 2?
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Meiosis 1 - As a primary oocyte. Pauses before birth and remains uncompleted until puberty and the moment when that particular primary oocyte is selected to be one of the follicles/eggs that develop.
Meiosis 2 - When secondary oocyte is released from follicle into fallopian tube, it is paused in Meiosis 2. Won't complete meiosis 2 unless fertilization occurs. |
Physiology: Gonads, Gametogenesis, Ovulation and Fertilization.
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During oogenesis what is formed along with a polar body at the two different divisions when a polar body is formed?
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1. Secondary oocyte and a polar body in follicle.
2. Mature ovum and secondary polar body in Fallopian tube, after fertilization. |
Physiology: Gonads, Gametogenesis, Ovulation and Fertilization.
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Where does estrogen production occur in males and females and by what cells?
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Females - Estrogen produced by developing follicles in the ovaries, the corpus luteum, and the placenta. Also in the granulosa cells of the ovaries.
Men - Sertoli cells aromatize testosterone produced by the Leydig cells to estrogens. |
Physiology: Gonads, Gametogenesis, Ovulation and Fertilization.
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What spaces do the sacrospinous and sacrotuberous ligaments create?
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Sacrotuberous ligament closes off the lesser sciatic foramen, and the sacrospinous ligament runs through the centre of this space to the ilial spine to create the separation between the two.
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Pelvic Anatomy Lecture
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The pelvic floor/diaphragm separates out what two areas?
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The pelvic cavity from the perineum.
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Pelvic Anatomy Lecture
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What is the muscle that forms a sling around the rectum/anal canal called?
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This is the u shaped muscle surrounded by the pubococcygeus. Puboractalis or Puborectal Sling
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Pelvic Anatomy Lecture
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What part of the tendinous arch do the two main muscles of the levator ani originate?
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Pubococcygeus originates from the anterior half of the tendinous arch.
Iliococcygeus originates from the posterior half of the tendinous arch. |
Pelvic Anatomy Lecture
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Describe the position/orientation of te coccygeus muscles.
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Flat triangular sheets that lie in the same plane as the levator ani. Form the posterior part of the pelvic floor.
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Pelvic Anatomy Lecture
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What is the urogenital diaphragm?
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Very strong band that runs between the ischial and pubic rami. Double layer of fascia, serves as an attachment for many of the external genitalia.
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Pelvic Anatomy Lecture
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What are the sources of autonomic nerve supply to the pelvis?
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Sympathetic and parasympathetic nerve fibers come from the Right and left pelvic (inferior hypogastric) plexus.
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Pelvic Anatomy Lecture
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What reflexes do the Right and left pelvic (inferior hypogastric) plexus' control?
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Micturition, genital, and defecation reflexes.
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Pelvic Anatomy Lecture
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Where does referred pain from the uterus go?
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Pain from the body of the uterus is conveyed along sympathetic fibers via the presacral plexus to the upper lumbar segments of the cord.
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Pelvic Anatomy Lecture
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What is prenatal care? What is its purpose?
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Medical and nursing care recommended for women before and during pregnancy. Want to detect potential problems early, to prevent potential problems, and to direct care to specialists as appropriate.
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The Prenatal Record
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How much preconception folate should a woman be taking?
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1. No risk factors - 0.4mg/day
2. Neural Tube Defects risk factor (diabetes, on anti-epileptic meds, anti-folate meds, alcohol over use, liver disease) or prior pregnancy affected with folate sensitive anomaly - 1 mg/day 3. Personal or PObHx of NTD - 4mg/day |
The Prenatal Record
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When would you consider using ultrasound dating to help date a woman's pregnancy (instead of just calculating based on her LMP)?
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Uncertain LMP, Abnormal/irreglar menstrual cycles, <3 cycles since last pregnancy, <3 cycles since discontinuation of hormonal contraceptives
*U/S done EARLIER are more accurate than those done later. |
The Prenatal Record
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Explain the meaning of GP notation.
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Gravida - total number of pregnancies for the patient, including this one.
Para - Total number of deliveries >20 weeks gestation (*multiple gestations = twins, triplets = 1) |
The Prenatal Record
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Explain the distinction between Abortus, Stillbirth, and Neonatal death as it fits into the Gravida Para notation.
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Abortus - spontaneous or therapeutic losses <20 weeks
Stillbirth (SB) - Fetal death > (or equal to) 20 weeks Neonatal deaths (NND) - Early (<7 days of age) or late (<28 days of age) |
The Prenatal Record
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In the prenatal record, under Obstetrical Hx, Complications are divided into three categories. WHat are these categories and what are some examples of each?
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1. Antepartum (before birth) - IUGR, HTN, abruption (placental lining separates from uterus)
2. Intrapartum - Induction of labor, operative vaginal delivery 3. Postpartum - PP depression, NICU admission, postpartum hemorrhage |
The Prenatal Record
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What is WinRho?
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WinRho is an injection of antibodies administered with every pregnancy, when the mother is known to be Rh-negative. It destroys circulating blood cells from the baby before mother's body can mount its own (and therefore lasting) immune response.
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The Prenatal Record
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What are some things that would come up on the prenatal record that might indicate a need for a genetic screen?
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Advanced maternal age (Age >35 at delivery)
Hx of congenital abnormalities/birth defects Hx of inherited disease/disorder Hx of diabetes Ethnic risk Cosanguinity |
The Prenatal Record
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What is Maternal Serum Testing? Who gets it? When is it done?
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Offered to all women regardless of age. Looks for fetal aneuploidy and NTD.
1. First trimester MST (9-13 weeks). Pregnancy-associated plasma protein A (PAPP-A) and free Beta hCG 2. Second trimester MST (15-20 weeks). Alpha-fetoprotein (AFP), estriol, and free Beta HCG |
The Prenatal Record
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Some pregnant women are given an option to have an Early Pregnancy Review ultrasound at 11-13 weeks. Who is offered this? What are they looking for on u/s?
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Women with risk factors (advanced maternal age, multiple gestation, medical comorbidities, IVF, recurrent pregnancy loss, poor PObHx). are offered this u/s. U/s assesses viability, dating, early anatomic development and nuchal translucency.
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The Prenatal Record
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All women are offered a routine second trimester obstetrical u/s at 18-21 weeks. What are you looking for at this point?
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Fetal biometry (measurements of head, tummy and leg used to date fetus), Amniotic fluid volume, Placentation, Anatomical review for anomalies, Markers for fetal aneuploidy.
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The Prenatal Record
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Antenatal Screening is offered to all women at 24-28 weeks, and then again at 35-37 weeks. What are they looking for at each of these time points?
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At 24-28 weeks = Hb, Diabetic screen, Maternal ab screen
At 35-37 weeks = Group B Stretococcus (GBS). Done with a vaginal-rectal swab. To determine need for intrapartum antibiotic prophylaxis to prevent early onset neonatal GBS disease. |
The Prenatal Record
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What is appropriate gestational weight gain?
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Normal weight mother (BMI 18.5-25) = 25-35 lb.
Overweight (BMI 25-30) = 15-25 lb. Obese (BMI >30) = 11-20 lb |
The Prenatal Record
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At the postpartum visit you should be asking about the B's. What does this include?
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Baby, breasts, bladder, bowels, bleeding, birth control, blues
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The Prenatal Record
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When should the initial prenatal visit occur? What happens?
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Should occur as soon as pregnancy is suspected in order to offer comprehensive antenatal screening.
At this time you complete a prenatal record and requisitions for initial investigations. |
The Prenatal Record
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What date are elective terminations done up until in NS? What are the exceptions?
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Terminations are done up until 16-18 weeks. <16 weeks would do dilation and evacuation. Over 16 weeks would induce delivery.
For medical risks = throughout pregnancy. For Down syndrome or other abnormalities = up to 24 weeks. After that need two Doctors consent. |
The Prenatal Record
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What do maternal serum tests in the Maritimes screen for?
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Down syndrome, Neural Tube Defects, Trisomy 18 and 13, Smith-Lemli-Opitz syndrome (SLOS; collection of symptoms linked to a defect in cholesterol synthesis)
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The Prenatal Record
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What are the different feedback loops that estrogen and progesterone are involved in the female HPG axis?
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Estrogen and progesterone both negatively feedback on pituitary and hypothalamus. Except at high doses of estrogen - which signals for the release of LH causing the surge. Excess progesteron under certain circumstances (like pregnancy) can also have a positive feedback effect.
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Case 1 - Amenorrhea
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Distinguish between embyological and gestational age.
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Embryological - length of time since fertilization. More accurate, rarely used clinically.
Gestational Age - Dating pregnancy from the first day of the LMP. Includes a two week long period of time prior to conception. This is what is used clinically. |
Case 2 - Maternal Screening
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How would you change a woman's estimated due date if her menstrual cycle was 5 weeks long? Why?
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Ovulation/conception usually occurs two weeks before the menstrual period begins, irrespective of menstrual cycle length (luteal phase is relatively constantly 14 days, follicular stage is what varies). Therefore for the “average” 28-day menstrual cycle, the added time period from the LMP to ovulation is 2 weeks. If the patient’s menstrual cycle was 5 weeks long, the period between the LMP and ovulation/conception would 3 weeks. So for a woman whose cycle is 5 weeks long, you would subtract a week from your gestational age, because fertilization actually happened a week later than you thought it did. Or add a week to EDC.
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Case 2 - Maternal Screening
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What is the due date with gestational age (EDC)? Embryological age? What is considered to be gestationally 'at term'?
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Gestational EDC - 40 weeks
Embyological due date - 38 weeks Gestationally at term is a baby born anytime between 37-42 weeks. |
Case 2 - Maternal Screening
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What is the definition of advanced maternal age? What risks does this pose in terms of fertility, pregnancy, and the fetus?
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AMA is traditionally defined as a pregnancy in a woman who will be 35 years old or greater at delivery. See:
- increased frequency of chromosome abnormalities due to non-disjunction - a higher incidence of infertility and miscarriage. - woman faces increased risks of medical complications (chronic hypertension, gestational diabetes) and caesarean delivery. |
Case 2 - Maternal Screening
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In the Maritimes, all women are ideally offered a combined first and second trimester serum screening. When is the blood drawn for the 1st and 2nd screen?
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First blood draw from the beginning of the 9th week to the end of the 13th weeks Second blood draw between the beginning of the 15th and end of the 20th week of gestation.
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Case 2 - Maternal Screening
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What extraembryonic structures will form from the epiblast?
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The amniotic ectoderm only.
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Case 2 - Maternal Screening
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What are the different tissue types present in primary, secondary and tertiary villi?
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1. Primary = Proliferations of the cytotrophoblast, which then protrude into the syncytiotrophoblast
2. Secondary = Extra embryonic mesenchyme (embryoblast) grows into the layer of ST and CT to form a core 3. Tertiary (Chorionic) villi = Networks of capillaries develop in this mesenchyme core and maternal fetal circulation is established. |
Case 2 - Maternal Screening
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Most of the controversy about embryonic stem cells comes from pluripotent cells in which region of the developing embryo?
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The inner cell mass (the embryoblast). These cells are fated to create all of the embryonic structures and all of the placental tissues and fetal membranes other than the syncytiotrophoblast and cytotrophoblast.
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Case 2 - Maternal Screening
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When you do chorionic villi sampling, what do you aspirate?
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Tertiary villi from the chorion frondosum and are composed of the mesenchymal core, cytotrophoblast and an outer layer of syncytiotrophoblast. Fetal capillaries and maternal decidua are also aspirated.
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Case 2 - Maternal Screening
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When (fetal age) can you do chorionic villi sampling and amniocentesis? How long do the results take?
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CVS = gestational age of 10 weeks and 13 weeks and 6 days. Easiest from 12-13 weeks. Results are usually available in 2-3 weeks. Woman can get results before visibly pregnant.
Amnio = Done after 15 weeks and results take 3 weeks. |
Case 2 - Maternal Screening
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What are the risks associated with CVS and amnio?
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Amnio - Miscarriage (1 in 200-500, closer to 1:500 at 20 weeks vs. 1:200 at 15 weeks), Maternal infection (rare), injury to the fetus with the sampling needle (very rare, esp. with u/s guidance which is std. practice)
CVS - Miscarriage (1:100). Possibility of maternal cell contamination and the possibility of diagnostic ambiguity requiring follow-up amniocentesis. CVS before 10 weeks of gestational age have an increased risk of congenital limb abnormalities. |
Case 2 - Maternal Screening
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What does the cytogenetic nomeclature : 47, XY, +10 mean?
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In the cell examined there were 47 chromosomes instead of the expected 46 chromosomes. The “+10” identifies the additional chromosome as being Chromosome 10, therefore this cell contained three Chromosome 10s, instead of the expected two.
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Case 2 - Maternal Screening
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Although maternal cell contamination is a risk of CVS, it does not often pose a problem in practice. Why is this?
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In any technique where you are doing cell culture, maternal decidua has a low mitotic index so fetal cells overwhelm. Usually.
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Case 2 - Maternal Screening
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When you do a CVS can prepare the cells in two separate ways. What are these ways and which is more representative of the fetus?
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Direct preparation samples the cytotrophoblast. Cultured preparation mainly samples extra embryonic mesoderm, from the mesenchymal core of the villus.
The extra embryonic mesoderm originally derives from the inner cell mass (the embryoblast) so more representative of the fetus. |
Case 2 - Maternal Screening
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What cell types does an amnio sample? Is a CVS or amnio more representative of the fetus?
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The amniocentesis results will be more reflective of the fetus itself. The cells present in amniotic fluid are generated from the fetus (most common type is fibroblasts exfoliated from skin) or at least very late developing extra embryonic tissue. Only a few viable cells are present in any specimen, thus, a long culture time is needed to get enough metaphases for diagnosis.
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Case 2 - Maternal Screening
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What does Primigravida mean? Nulliparous? Multiparous?
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Primigravida = A woman pregnant for the first time. Nulliparous = Never pregnant or never carried a child beyond 20 weeks. Multiparous = A woman who has given birth two or more times.
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Case 3 - Down syndrome
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Physical features of individuals/infants with Down Syndrome?
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- Physical characteristics: Hypotonia (low muscle tone, often with low muscle strengeth). Brachycephaly with a flat occiput (flattened and widened back of the head). The neck is short, with loose skin on the nape. The nasal bridge is flat; the ears are low-set and have a characteristic folded appearance and the mouth is open, often showing a furrowed, protruding tongue. Characteristic epicanthal folds and upslanting palpebral fissures (separation between upper and lower eyelids). Hands are short and broad, often with a single transverse palmar crease (“simian crease”).
- Developmental delay. - Congenital heart disease (in 1/3 live born Down syndrome infants). Certain malformations, such as duodenal atresia and tracheoesophageal fistula, are much more common in Down syndrome than in other disorders. |
Case 3 - Down syndrome
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What are the possible chromosomal abnormalities in Down syndrome? Briefly describe.
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- Standard trisomy 21 (eg. 47,XY,+21) - An extra chromosome 21 from meiotic non-disjunction or failure of the chromosome pairs to separate during gamete formation is present in about 95% of individuals with DS.
- Robertsonian translocation - About 4% have 46 chromosomes, one of which is a robertsonian translocation between 21q and the long arm of one of the other acrocentric chromosomes (typically chromosome 14 or 21). 46,XY,rob(14;21), +21 - Mosaic - About 1% are mosaic, with a cell population containing both normal and trisomy 21 karyotype. |
Case 3 - Down syndrome
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What is talipes equinovarus?
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Clubfoot. Foot turns inward and downwards
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Case 4 - Malformation
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What dates are normally referred to as 'embyonic age'? 'Fetal age'? Period of fetal viability?
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-Embryonic period is the time period from conception until when the germ layers finish developing into primitive definitive fetal organ systems. From 2 weeks post LMP until the last day of the 9th week (gestational Age).
-Fetal period - Except for CNS, most of the fetal structures are present by this point and they are just growing. 1st day of week 10 gestational age to birth. During the embryonic period, the gestation is referred to as an “embryo”, and after 10 weeks gestational age, the designation is changed to a “fetus” - The beginning of the 24 weeks is usually labelled as the beginning of the period of viability. This degree of prematurity is associated with significant mortality and morbidity, with death occurring in 50% of infants born at 24 weeks, and 50% of the survivors having a major adverse outcome (defined as blindness, deafness, seizure or mental retardation). |
Case 4 - Malformation
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Distinguish between disruption, deformations and malformations types of congenital malformation?
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- Disruptions = Arises due to the destruction of already existing and otherwise normal tissue. (eg. constriction by an amniotic band which causes ischemia and therefore destroys tissue).
- Deformation = Arises because of mechanical force applied to an already formed and otherwise normal fetal structure. (eg. uterine fibroid putting pressure on a fetal leg causing talipes equinovarus). For both of these, normal fetal structures have to be already present to be damaged. Therefore disruptions also generally occur in the 2nd or 3rd trimesters. As much of the causative aetiology is mechanical force due to fetal growth, the 3rd trimester is again the highest risk time period. Malformation - intrinsic abnormalities in pattern formation (the process of the embryonic specification of organs and their localization) (eg. thalidomide causing limbs abnormalities). As pattern formation is almost complete by the end of the embryonic period (EXCEPT FOR THE CNS), almost all malformations arise then. |
Case 4 - Malformation
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What are the three placental arrangements of the chorion and amnion we see with MZ twins and how does each develop? What about in DZ twins?
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Dichorionic, Diamnionic - Single conceptus that undergoes fission before blastocyst stage, separate placentas form.
Monochorionic, Diamnionic - Separation of inner embryonic cells before amniogenesis results in a single placenta with two amnions (vascular connections between the two at the level of the placenta. Predispose to thrombi). Monochorionic, Monoamnionic - Separation of embryonic cells before development of the embryonic axis results in a single placenta with one amnion (latest possible split before starts forming conjoined twins). DZ twins are dichorionic and diamnionic - formed from two fertilized eggs, two placentas develop, each with chorion and amnion. |
Case 4 - Malformation
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What is congenital ileal atresia? Aetiology?
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A 'disruption' where there is narrowing or absence of the ileum. Most congenital GI atresia arises from either thrombi or emboli causing ischemia and death of a short section of bowel and usually the associated mesentery.
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Case 4 - Malformation
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What is hydranencephaly? Common aetiology?
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Hydranencephaly = A rare congenital abnormality in which the fetal cerebral hemispheres are absent and instead replaced with CSF. While compatible with signs of life after birth (as the brainstem is often intact), this condition is associated with an increased risk of intrauterine demise. Believe hydranencephaly results from an in utero vascular (eg. clot) event, which leads to ischemia and involution of the already formed cerebral cortex.
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Case 4 - Malformation
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True or False: If you test both the parents of a child suspected to have CF using a panel looking at the most common mutations and they all come back normal, you can test the baby PP using blood from the umbillical cord?
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Faslse - Fetal testing for a CF mutation will only be reliable if the CF mutations can be identified in them. Otherwise won't find anything new in baby.
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Case 5 - Cystic Fibrosis
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What are some ways to diagnose CF after birth?
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1. Sweat chloride test - Look for Cl levels over a certain threshold to test positive.
2. Transepithelial nasal potential difference - Use in children older than 6. Drip solution into nose and look at uptake of sodium/chloride. 3. Newborn screening using immunoreactive trypsinogen (IRT) - Preformed on blood spots. Trypsinogen is made in the pancreas, in CF levels are increased because of abnormal pancreatic duct secretions. Just a screen. |
Case 5 - Cystic Fibrosis
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There are >1000 CF gene sequence variants within the region that codes for the CFTR gene. What is the most common one of these?
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70% of all CF alleles is deltaF508, a three nucleotide deletion causing a loss of phenylalanine (f) residue at position 508 within the protein. Causes misfolding of the CFTR protein and keeps it from incorporating into the cell membrane. Results in classic CF.
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Case 5 - Cystic Fibrosis
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What is an echogenic bowel? What can it indicate in a fetus?
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Echogenic bowel = fetal bowel with either focal or multifocal areas of echogenicity equal or greater to that of surronding bone. It is considered a prenatal marker for CF, chromosomal aneuploidy, and numerous other abnormalities. But in 90% of cases the pregnancy is totally normal.
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Case 5 - Cystic Fibrosis
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How long does the normal pubertal sequence of accelerated growth, breast development, pubarche and menarche take, on average?
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On average, 4½ years
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Case 6 - AIS
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What are the four compartment systems on which proper menstruation depends?
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Compartment 1: Disorders of the outflow tract or uterus
Compartment 2: Disorders of the ovary Compartment 3: Disorders of the anterior pituitary Compartment 4: Disorders of the CNS |
Case 6 - AIS
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What is Mullerian agenesis (Mayer-Rokitansky-Kuster-Hauser syndrome)?
|
A congenital malformation characterized by a failure of the müllerian ducts to develop, resulting in a missing uterus and fallopian tubes and variable malformations of the upper portion of the vagina. Presents with amenorrhoea and an absent or hypoplastic uterus. The vagina may also be totally absent or hypoplastic. If there is an endometrial cavity, cyclic abdominal pain, in response to endometrial build up may be a symptom. These individuals however have ovaries and a normal female karyotype. In such women normal ovarian function occurs and normal body hair growth would be apparent.
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Case 6 - AIS
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At what point in development do we see differentiation in external genitalia? WHat happens to create male/female genitalia?
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The external genitalia, up until the eighth fetal week are neutral primordia, able to develop into either male or female structures depending on gonadal steroid hormone signals. Under the active influence of androgen from the Leydig cells of the testes, the genital tubercle forms a penis, labioscrotal folds fuse to form a scrotum and folds of the urogenital sinus form the penile urethra. Without androgen stimulation (eg. female, AIS) - the folds of the urogenital sinus remain open, forming labia minora. The labioscrotal folds form the labia majora and the genital tubercle forms the clitoris, the urogenital sinus differentiates into the lower vagina and urethra. The lower vagina is thus formed as part of the external genitalia.
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Case 6 - AIS
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What is the difference between complete and incomplete/partial AIS? When are they each usually diagnosed?
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Incomplete AIS forms a spectrum of conditions manifest by incomplete virilization of male external genitalia from hypospadias, undescended testes, bifid scrotum (separation of the two halves of the scrotum) to a phenotypic fully female appearance. Incomplete AIS is more likely to be diagnosed in early childhood, whereas complete AIS usually presents later with delayed onset of puberty.
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Case 6 - AIS
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Why would a female with complete AIS express an X-linked recessive condition?
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Because they are chromosomally male, although phenotypically female - would express X-linked conditions like a man because only have one X chromosome.
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Case 6 - AIS
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What is the pathophysiology of AIS?
|
Testes secrete androgen normally, but there is end-organ unresponsiveness to androgens resulting from absence of androgen receptors in the cytosol of appropriate target cells.
A different form, with a different disease progression can be due to absence of 5 alpha reductase which is responsible for converting testosterone to DHT (potent form of testosterone). |
Case 6 - AIS
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A baby born with ambiguious (halfway between male and female) genitalia may have Incomplete AIS or Congenital Adrenal Hyperplasia. What is CAH? How does it occur?
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The fetus produces ACTH but is unable to produce cortisol. The stimulation by ACTH results in other steroid hormones being produced in excess. The adrenal produces excessive amounts of adrenal androgens. Usually doesn't affect boys too much, but in baby girls it can masculinize the genitalia to the extent the clitoris resembles a penis. If the block is a 21-hydroxylaze deficiency (the most common form of CAH) the baby is at risk of a salt losing crisis because mineralocorticoids are also affected. **Always measure electrolytes in this case!
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Case 6 - AIS
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What is a Neural Tube Defect?
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Any congenital abnormality that arises from a failure of the neural folds to close and form a neural tube during embryonic development. NTD: anecephaly, encephalocele, spina bifida.
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Case 7 - NTD
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What is the relationship between anti-epilepsy meds and birth defects?
|
All anti-epileptic medications that are adequately studied appear to be teratogenic to a degree, and many are associated with an increased risk for neural tube abnormalities in particular. However, it appears that the teratogenic risk associated with Valproic acid is particularly high (most important is that it causes neural tube defects). Better to be on an anti-epileptic than to have a seizure during pregnancy in most cases.
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Case 7 - NTD
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What do you look for on a maternal serum screen in order to create a risk assessment for open neural tube defects?
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AFP. This is produced by the fetal liver and yolk sac and is present at relatively high concentrations in the fetal fluids. A small amount of fetal AFP enters the amniotic fluid and then crosses into maternal circulation. The concentration of AFP in the amniotic fluid will increase if there are ectopic sources of fetal fluid loss, such as an open NTD, gastroschisis or congenital skin abnormalities. Fetal renal dysfunction can also lead to the increased fetal excretion of AFP. Basically acts like albumin, and anything which would cause albumin to leak (eg renal damage or escape of serious fluid to the skin), will result in an increased fetal excretion of AFP.
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Case 7 - NTD
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What are two non-pathogenic and common causes of an increased Alpha-fetoprotein on maternal serum screen?
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Other causes of an increased maternal AFP are multiple gestations and incorrect dates (very date dependent).
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Case 7 - NTD
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Distinguish between Spina bifida occulta, a meningocele and a meningomyelocele?
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Spina bifida occulta - Failure of fusion of the posterior elements of the vertebrae. Often undetected and asymptomatic.
Meningocele - The protruding sac contains meninges and spinal fluid. Can be closed or open. If closed has better prognosis with respect to preservation of lower spinal cord function because amniotic fluid is harmful to the CNS. Myelomeningocoele - The protruding sac contains meninges, spinal cord and spinal fluid. |
Case 7 - NTD
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What is neurulation (briefly)? What happens if it doesn't occur properly?
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Neurulation - The process by which the ectoderm derived neural plate forms a neural tube. The neuroectoderm is the midline region of the ectoderm germ layer. The edges of the neuroectoderm grow upward and towards each other. Eventually the two folds fuse. In the process, a continuous sheet of ectoderm is formed above the neural tube, which will eventually create the skin overlying the neural tube. Likely there are several different primary sites of neural tube closure initiation. From these sites of primary closure, the neural tube then “zips up” both rostrally and caudally, leading to creation of a closed tube. Failure of the tube to close leads to the creation of a NTD. If it is the cranial neuropore that fails to close, this would result in anencephaly, if it is the caudal neuropore, this would lead to spina bifida.
NB- the risk factors for anencephaly and spina bifida are the same and that the occurrence of one increases the risk for the other to occur in future pregnancies |
Case 7 - NTD
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What two groups of cells are derived from the neuroectoderm? In general, what mature structures are derived from these two cell populations?
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The process of neurulation leads to the creation of the neural tube which will form the:
1. Central Nervous System (CNS) 2. Neural crest. Goes on to form forms the enteric nervous system, melanocytes, the adrenal medullary and the peripheral nervous system |
Case 7 - NTD
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What embryonic structure do vertebrae come from?
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Vertebrae are formed from the sclerotome component of the somites.
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Case 7 - NTD
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Why does a failure of the neural tube to close cause abnormalities of the vertebrae?
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Formation of the vertebrae requires two process to be completed in sequence. First the neural tube most close to “join” the left and right sides of the posterior midline, and only if this is successful can the cells of the somites complete their migration and form the posterior vertebrae. However the later process could go wrong even if the neural tube formed normally.
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Case 7 - Neural Tube Defects
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What is the big aetiological difference between spina bifida occulta and open spina bifida -like abnormalities?
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In spina bifida occulta (very common - around 2% of the population), there is a localised failure of at least one posterior neural arch to form, but both the meninges and spinal cord are unaffected. Occulta occurs because the sclerotome cells fail to migrate or proliferate into the spinal arch. Results from a focal abnormality in the migration of the sclerotomal cells of the somite. It is a distinct, unrelated malformation from a open case of spina bifida. As occulta is a distinct process, a family history of this malformation does not increase the chance that a relative will have a neural tube disorder (NTD).
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Case 7 - Neural Tube Defects
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What is emergency contraception? What are the three main options?
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Used after intercourse to prevent pregnancy. Mainly modify endometrium or delay/inhibit ovulation. NOT INDUCING ABORTION.
1. Yuzpe Method 2. Plan B (Levonorgestrel) 3. Copper IUCD |
Reproductive Choice
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Describe the three options for emergency contraception.
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1. Yuzpe Method - Take 2 Ovral (high dose OCP- estradiol and levonorgestrel) spaced 12 h apart. High dose estrogen so very nausating. Recommend gravol. 95% effective if taken within 24h, decreases after that. 75% effective overall
2. Plan B (Levonorgesterel), Two pills, 12 hours apart. Less nausea-inducing so overall slightly better efficacy (85% overall). Again, better if you take it sooner. OTC, no prescription required. 3. Copper IUCD - Most effective within 5 days (99.9%) of intercourse but can be used up to 7 d. Must be inserted by a health care professional. |
Reproductive Choice
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What are your termination of pregnancy options and what are the time frames in which they can be used?
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1. Methotrexate and Misoprostol. Medical Termination. Generally done <8 weeks.
2. Vacuum Aspiration <10 weeks, usually done <7. Not commonly done here. **3. Suction Dilatation and Curettage (D&C). Done <13 weeks. Gold standard - most common method. Used in 1st and 2nd trimester. 4. Dilatation and Evacuation (D&E) - Can be done from 13-22+ weeks. Generally only done until 15 weeks. **5. Misoprostol (uterotonic Agent that induces labor). Most common practice >15 weeks. |
Reproductive Choice
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What is RU-486?
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It is a method of medical temination of pregnancy. Not licensed for use in Canada. Used for GA 49-63 d. (7-9 weeks)
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Reproductive Choice
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What is the main method of medical termination of pregnancy in Canada? Pros/cons? Efficacy?
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Methotrexate (chemo drug, targets rapidly dividing cells) and Misoprostol (dilates cervix, induces labor). Sometimes use misoprostol alone. Do a bHCG/US to ensure evacuation of uterus.
*Pts have to commit to follow up though because it is a course of several drugs and if patients don't complete it is a teratogen. Can also get pain and GI upset. Also longer interval of completion (time between taking drugs and losing pregnancy). 95% effective in terminating pregnancy. |
Reproductive Choice
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What is the manual vacuum aspiration method for terminating pregnancy?
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Usually done at <7 weeks. Very rarely done now. Can be preformed in physician's office. But up to a 10% failure rate with continuing pregnancy. Critical to confirm chorionic villi/gestational sac removed to ensure procedure completed.
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Reproductive Choice
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What is the suction D&C method for terminating a pregnancy?
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Dilatation and Curettage (remove tissue by scraping or scooping). Most commonly used procedure (safest and Gold std.) for under 13 weeks. Outpatient procedure but done in hospital/clinic setting.
Primarily done under local anesthetic. Do a speculum exam and freeze around the cervix. +/- Conscious sedation. Cervix dilated then suction D&C. Examine all products of conception for completeness. |
Reproductive Choice
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What is the D&E method for terminating a pregnancy?
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Dilatation and Evacuation. Done later than D&C. Primarily general anaesthesia. Cervix dilated and softened, suction procedure and instrumental evacuation of uterus. Use u/s guidance for safety and to assess completeness.
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Reproductive Choice
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Uterotonic agents are used to induce labour in pregnancy termination. How does this work?
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This is the most common practice >15 weeks. Can be done +/- medication to ensure birth is a stillbirth (eg. meds to stop heart). generally takes between 12-72 hours (90% deliver within 48h) to complete and require hospital admission.
Give meds to induce labor (gold std is 2-10+ doses of misoprostol every 4-6h; can also use PGE2 (prostin)). |
Reproductive Choice
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What are some side effects of inducing labor in pregnancy termination?
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- SE of meds (fever, chills, shakes, GI complaints)
- Bleeding (1% require transfusion) - Some retain the placenta (may have to do a D&C to remove it) - Uterine rupture (very rare) <1% have a serious complication, <1/100,000 die. |
Reproductive Choice
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What are some of the immediate and delayed complications of the D&C and D&E methods of TOP?
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Immediate: Hemorrhage, cervical shock (vasovagal shock rxn when cervix dilated), cervical injury, uterine perforation, hematometra (blood in uterus).
Delayed: Failed attempt, retained tissue, infection. |
Reproductive Choice
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What are adverse pregnancy outcomes that come from a termination of pregnancy?
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No increase in infertility, ectopic pregnancy, spontaneous abortion, adverse outcomes.
No increase in preterm birth, however number of procedure and cervical trauma increase risk of placenta-previa - same rate as previous spontaneous abortion. |
Reproductive Choice
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What are the three big categories of renal mass types? Major examples form each?
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Assume a renal cell carcinoma until proven otherwise.
1. Malignant: Renal cell carcinoma, urothelial carcinoma (cancer arising in the transitional epithelium - a tissue lining much of the urinary system), Wilms' tumor (more common in kids), mets 2. Benign - simple cyst (by far most common cause of renal masses), AML (benign but can bleed) 3. Inflammatory - Abscess, infected cyst. |
Pearls of Urology
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What imaging could you do for a renal mass? Pros/cons of each?
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1. Ultrasound - No contrast or radiation, can differentiate between cyst and solid. But less info.
2. CT Scan - Better for staging, more detail/can see smaller structures. But - requires contrast and radiation. 3. MRI - limited role initially but can be useful in invasive tumors/complex cysts. Very rarely used overall. |
Pearls of Urology
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Renal cell carcinomas are the most lethal of the urologic malignancies and not uncommon. How do they normally present?
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Classic triad- Flank pain, hematuria, and palpable mass. Not usually picked up this way any more.
Majority picked up as 'incidentalomas' while imaging for another issue. |
Pearls of Urology
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How do you treat renal cell carcinomas?
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Either total or partial (more difficult to do partial than total) nephrectomy.
Chemo and radiation largely ineffective. Even with metastatic disease, removing the primary shows some benefit. |
Pearls of Urology
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What is hydronephrosis? How does it usually present?
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Urine gets backed up into kidney, causing it to swell. Occurs when outflow obstructed in some way. Depending on whether acute or chronic, can see sudden onset of one-sided flank pain, nausea and vomiting. Can be febrile with have hematuria.
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Pearls of Urology
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What causes hydronephrosis?
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Extrinsic: UPJ obstruction (ureteropelvic junction is a blockage in the area that connects the renal pelvis to the ureters), Aneurysm, Tumor/mass effect, Pelvic organ prolapse, Pregnancy.
Intrinsic: Stones, Urothelial carcinoma, stricture, Blood clot. |
Pearls of Urology
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What lab tests/images would you do with a patient who presents with severe flank pain who you suspect hydronephrosis? Pros/cons of different types of imaging in this case (hydronephrosis)?
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Labs: urinalysis, +/- culture, creatinine, electrolytes.
Imaging: US (can see hydro but might not detect stone), CT (Gold std. for stones, no contrast req'd, but expensive and over-used), IVP (mostly replaced by CT), Retrograde pylograms (inject dye up ureters towards kidney, take x-rays. Pt usually asleep, can use in pt. allergic to iv contrast) |
Pearls of Urology
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When is a suspected obstruction/hydronephrosis an emergency?
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In the presence of a fever or renal failure get an urgent urology consult.
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Pearls of Urology
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What two findings of hematuria are worrying?
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1. Gross, painless hematuria (negative culture)
2. Microscopic hematuria (2RBC/hpf on two separate urinalysis - in the absence of menses, UTI, instrumentation, recent trauma) |
Pearls of Urology
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What are the two most common causes of hematuria? In what 3 regions?
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In the Kidney, Ureter/Bladder, Prostate/Urethra - can have Stones and tumors.
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Pearls of Urology
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What are the risk factors for transitional cell carcinoma (urothelial cell or bladder cancer)?
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-Sex (3:1 men to women)
- Age (rare under 50) - SMOKING = biggest risk factor for bladder cancer. - Also chronic cystitis and pelvic irradiation |
Pearls of Urology
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How does transitional cell carcinoma (urothelial cell or bladder cancer) usually present?
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- 85% have painless hematura (gross or microscopic - 2 RBC/hpf on 2 seperate urinalysis)
-Irritative voiding symptoms (almost never without hematuria) - Flank pain - Pelvic mass |
Pearls of Urology
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How do you manage bladder cancer?
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Depends on staging:
Low Grade: Surveillance +/- Intravesical treatments High Grade (depends on whether metastatic and whether it has invaded muscle): Chemo, Radiation, Surgery or a combo. Once metastatic bladder cancer use chemo and radiation but primarily Palliative. |
Pearls of Urology
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What tests/images would you order with hematuria?
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Upper and lower urinary tract evaluation (urology referral)
-Do a cystoscopy (tube inserted thru urethra into bladder) and an U/S, or a CT - IVP can be an option with gross hematuria and normal U/S. |
Pearls of Urology
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What sort of physical findings are you looking for on a physical exam of a man with testicular/scrotal pain?
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Observation: Swelling, asymmetry, testicular position, discoloration.
Palpation: Mass, Hydrocele (collection of fluid in the tunica vaginalis around the teste - presents as a painless swelling), position of testicle (horizontal lie) |
Pearls of Urology
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What labs/images would you order on a man with testicular/scrotal pain?
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Labs: Urinalysis/C&S (ALWAYS), and consider CBC and tumor markers (if testicular mass)
Images: Scrotal U/S - rule out torsion, testicular mass and abscess |
Pearls of Urology
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What is testicular torsion? How does it present?
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Occurs when the spermatic cord to a testicle twists, cutting off blood suply. Most common underlying cause in a congenital abnormality called 'a bell clapper deformity' wheere teste is inproperly affixed to spermatic cord allowing to to move too freely on its axis and become entangled.
Presents with acute onset of testicular pain and lower quadrant abdominal pain. Often swelling. Nausea and vomiting. Typically age 12-18, almost always under 30. |
Pearls of Urology
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What will you see on a physical exam with a testicular torsion? What is diagnostic?
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High riding testicle, horizontal lie, swelling and edema, absence of cremasteric reflex (not a specific sign, but if it isn't there you are worried). But physical exam is not very reliable. If you suspect torsion - urgent scrotal u/s (gold std.).
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Pearls of Urology
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What is the cremasteric reflex?
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Lightly stroke the upper inner thigh. Normal response is an immediate contraction of the cremaster master that pulls up the testicle on the side being stroked (only). Not present in testicular torsion)
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Pearls of Urology
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What is epididymitis? How does it present?
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Swelling of the epididydmis. Often caused by spread of bacterial infection from urethra or bladder. get pain, swelling, and erythema, usually with a gradual onset. May be associated with some dysuria or fever and chills. Will have a positive cremasteric reflex.
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Pearls of Urology
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What bacteria commonly causes epididymitis?
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Sexually active men <35 yrs - chlamydia, gonorrhea, E. coli
Men >35 yrs - usually gram neg. from urinary tract. Consider TB if exposure. |
Pearls of Urology
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Testicular cancer is the most common tumor in men ages 15 to 34. How does it normally present and how do you confirm the diagnosis?
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Usually palpate a solid mass. history of fairly rapid growth. May have some associated pain, but usually asymptomatic. Diagnose with US.
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Pearls of Urology
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What are some risk factors for testicular cancer?
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- Cryptorchidism (undescended testicle, increases risk 10x)
- Testicle atrophy - Family history of germ cell tumor |
Pearls of Urology
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What is the management of testicular cancer?
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Pretty good outcomes. Treat with orchiectomy, chemo, radiotherapy, retroperitoneal lymph node dissection.
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Pearls of Urology
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