Clinical Chemistry Ii Test 2 - Gonadal And Pregnancy Hormones

Front 1

What are Estrogens?

Back 1

Estrogens are C-18 steroid hormones derived from the ovarian follicle and adrenal glands

Front 2

What 3 estrogens are clinically significant?

Back 2

Estradiol (E2) -- predominant estrogen in non pregnant female
Estrone (E1) —metabolic product of estradiol
Estriol (E3) —predominant estrogen in pregnancy

Front 3

What is estradiol (E2)?

Back 3

Chief estrogen produced specifically by the maturing follicle within the ovary and causes secondary sexual characteristics

Front 4

What is estrone (E1)?

Back 4

Metabolic product of estradiol with little biological activity.

Front 5

What is estriol (E3)?

Back 5

Synthesized by placenta using precursor steroid that is synthesized by fetusHigh concentration in pregnancy suppress pituitary hormones which prevents ovulation
*Not used for pregnancy test because its present in small amounts in non-pregnant females. HCG is not.

Front 6

What is the gonadal androgen, testosterone?

Back 6

Testosterone is the chief male androgen secreted by the testes (production increases at puberty) and also (5%) from adrenal gland

Front 7

What are androgens?

Back 7

Androgens are a group of C-19 steroids

Front 8

What are the two most active androgens?

Back 8

The two most active androgens are testosterone (gonadal androgen) and androstenedione (adrenal cortical androgen)

Front 9

What is the chief female androgen?

Back 9

Androstenedione is the chief female androgen synthesized by adrenal cortex and ovaries.

Front 10

What is testosterone converted into in circulation?

Back 10

dihydro-testosterone (DHT) which has greater biological activity

Front 11

What are the functions of testosterone?

Back 11

maturation of genitals and secondary sexual characteristics (muscles & bone development, deep voice, hair distribution).
growth of male reproductive system, prostate and larynx including hypertrophy of larynx and initiation of spermatogenesis.

Front 12

What is progesterone?

Back 12

Progesterone is a C-21 steroid hormone.
Primarily a female sex hormone produced by the corpus luteum

Front 13

What are the functions of progesterone?

Back 13

Functions in growth and vascularization of uterine lining in preparation for implantation of a fertilized ovum.
Very high levels seen in pregnancy (due to placental synthesis) which helps suppress pituitary hormones to prevent menstruation during pregnancy.

Front 14

What percent of both E2 and testosterone is bound in circulation to plasma proteins, specifically to SHBG (sex hormone-binding globulin)

Back 14

97-98%

Front 15

Progesterone is 90-95% bound to CBG (Corticosteroid binding globulin). (T/F)

Back 15

True

Front 16

Where is gonadotropin releasing hormone (GnRH) produced?

Back 16

hypothalamus. tertiary gland

Front 17

GnRH causes which gland to secrete LH and FSH?

Back 17

pituitary. secondary gland

Front 18

Regulation occurs through both positive and negative feedback over a month in the mature female. In the mature male, the cycle spans a 24 hours. (T/F)

Back 18

True

Front 19

The posterior pituitary produces __________ for uterine contractions during labor and breast milk ejection during lactation.

Back 19

Oxytocin

Front 20

The anterior pituitary provides secondary level of control and stimulation of reproductive hormones through release of which gonadotropins?

Back 20

LH and FSH

Front 21

What are the primary reproductive organs?

Back 21

Ovaries and testes

Front 22

What causes the primary reproductive organs to release hormones?

Back 22

cells that respond to the binding of LH and FSH to specific cellular receptors causing the secretion of hormones such as estrogen and testosterone.

Front 23

What does FSH do?

Back 23

stimulates growth and mitosis/meiosis of gametes (ovum in the follicle of ovary, spermatogonia in testis) and synthesis and release of inhibin

Front 24

What does LH/ICSH do?

Back 24

LH = luteinizing hormone
ICSH = interstitial cell-stimulating hormone
Trigger the release of gametes by stimulating secretion of hormone by supporting cells (progesterone from corpus luteum in ovary, testosterone from interstitial cells in testis)

Front 25

In men, the negative feedback happens continuously. (T/F)

Back 25

True. Constant levels of FSH, LH, inhibin, and testosterone

Front 26

In women, the negative feedback happens ~ once every 28 days. (T/F)

Back 26

True. menstrual cycle

Front 27

Negative feedback of reproductive hormone in men.

Back 27

Decreased testosterone stimulates anterior pituitary to secrete FSH which stimulates spermatogonia to grow (spermatogenesis)

Decreased testosterone also stimulates pituitary to secrete LH which stimulates the production of testosterone (stimulates spermatogenesis)

Front 28

Negative feedback of reproductive hormone in females

Back 28

IncreasedFSH induces follicular development (resulting in ovulation) and E2 release – negative feedback

Increased E2 stimulates anterior pituitary to secrete LH which stimulates ovaries (after ovulation has occurred) to stop producing E2 and then induces maturation and rupture of follicle which releases its ovum. E2 increases following the release and the ruptured follicle becomes the corpus luteum that produces progesterone.

Front 29

What is menstruation?

Back 29

sloughing of uterine wall & its blood vessels because there was no fertilized ovum implanted resulting in discharge of blood and mucosal tissue from the vagina of a female.

Front 30

What is menopause?

Back 30

Cessation of menstruation in women is called Menopause
Lack of estrogen
Both FSH and LH increase

Front 31

What hormonal signals cause ovulation?

Back 31

These hormonal signals include hypothalamic stimulation of the pituitary by gonadotropin-releasing hormone, resulting in periodic secretion of LH and FSH by the pituitary gland.

Front 32

Normal female reproductive physiology

Back 32

As the FSH concentration rises at the beginning of each cycle, one dominant follicle is the most responsive to FSH and LH.
This follicle participates in the process of ovulation, or release of the oocyte to the fallopian tube.
Cells in the follicular lining are further stimulated by other hormones including LH to develop a lipid-rich mass surrounding the oocyte, called the corpus luteum.
The corpus luteum is further stimulated by LH and initiates the production of progesterone which plays a major role in maintaining the endometrial lining.

Front 33

Normal female reproductive physiology (part II)

Back 33

The fate of the corpus luteum is quite varied depending on the presence or absence of sperm cells.
If sperm cells are not present to fertilize the released oocyte, the corpus luteum degenerates and dies after about 10 days resulting in a drop in progesterone levels.
If sperm cells travel up from the vagina to the fallopian tubes and fertilize an oocyte, a zygote results.
The zygote travels down the fallopian tube to begin the process of division.
Pregnancy begins with implantation of the blastocyst in the endometrium of the uterus. The blastocyst produces hCG which stimulates the corpus luteum to continue production of hormones for 10-12 weeks until the placenta functions in that capacity.

Front 34

What are the two phases of the menstrual cycle?

Back 34

follicular and luteal

Front 35

Follicular phase

Back 35

The follicular stage is the early, named for the maturation of the follicle.
Early in this phase, LH levels begin to rise as well and together FSH and LH bind to the specific receptors of one dominant follicle.
Pituitary secretion of FSH occurs in response to hypothalamic secretion of GnRH. The pituitary also responds to the negative feedback control of low levels of circulating estradiol and progesterone that occur with the demise of the corpus luteum from the previous cycle. The pituitary is stimulated to begin secretion of FSH and LH for the next monthly cycle.

Front 36

Follicular phase (part II)

Back 36

As LH and FSH levels rise, the ovarian follicles produce estrogen, mostly estradiol.
Increasing levels of estradiol in the later days of the follicular phase trigger GnRH secretion followed by more LH secretion at mid-cycle. In addition, estradiol promotes thickening of the endometrial lining.
Ovulation occurs around day 14 of the cycle. At the time of ovulation the highest levels of LH, FSH and inhibin A exist in the sexually mature female.

Front 37

Follicular phase (part III)

Back 37

Ovulation occurs around day 14 of the cycle. At the time of ovulation the highest levels of LH, FSH and inhibin A exist in the sexually mature female.
The surge of LH and FSH that mark ovulation also cause various clinical signs and symptoms that can be used to predict ovulation including cervical mucous thickening and a slight rise in body temperature, measured in the morning before rising.

Front 38

Luteal phase

Back 38

After ovulation there is a shift into the luteal phase, named for the development of the corpus luteum from the lining cells of the mature follicle.

Front 39

Luteal phase (part II)

Back 39

The transition between the end of the luteal phase in one monthly cycle and the follicular phase of the next monthly cycle is marked by menses. Menses, or sloughing of the uterine lining results if pregnancy did not occur and the corpus luteum dies.
Decrease in progesterone and estradiol levels due to the destruction of the corpus luteum trigger the menses.
The first few days of menses are signaled by very low levels of the reproductive hormones, with FSH and LH levels beginning to rise again in the first few days of the new monthly cycle.

Front 40

What happens during pregnancy?

Back 40

If fertilization occurs, then zygote implants in uterine wall and immediately forms a tiny placenta that produces hCG, progesterone and estrogen. Progesterone inhibits secretion of LH and GnRH. Embryo produces E3-precursor which placenta converts to Estriol (E3)  inhibits secretion of FSH and GnRH

Front 41

What does hCG stand for?

Back 41

human chorionic gonadotropin

Front 42

How long does pregnancy last?

Back 42

40 weeks

Front 43

How does pregnancy happen?

Back 43

Sperm cells reach the oocyte by traveling up the vagina, into the uterus and out of the fallopian tubes to the region next to the ovary.
Fertilization occurs when the oocyte and sperm cell are united to form a zygote.
Fertilization occurs in the first few days following ovulation.
For the sake of determining gestation age, fertilization is thought to occur on day 14 of the cycle. The zygote travels down the fallopian tube toward the uterus, begins dividing and forms a ball of cells, the morula.
Around 5-6 days after conception, the morula enters the uterus and differentiates into a blastocyst that consists of a hollow, fluid-filled ball of cells with an inner cell mass at one end and surrounded by an outer cell layer.
The blastocyst implants in the uterus on day 6-8.

Front 44

What are the pregnancy markers?

Back 44

human chorionic gonadotropin (hCG)
human placental lactogen (hPL)
progesterone

Front 45

What does a pregnancy test test for?

Back 45

Serum or Urine beta-hCG tests for presence of placenta

Front 46

What is hCG?

Back 46

HCG is a dipeptide hormone; the alpha peptide is the similar to LH, TSH, FSH and other hormones, but the  peptide is unique.

This hormone is produced by chorionic villi of the implanted blastocyst and triggers the corpus luteum to release progesterone and estrogen. hCG helps maintain the uterine lining, the endometrium, with an adequate uterine blood supply until placental synthesis of progesterone begins.

Front 47

When is the earliest that hCG can be detected?

Back 47

Detectable levels of hCG begin at about 22 days.
During the first trimester, serum hCG level doubles every 2 days reflecting growth and healthy development of the placenta.
once progesterone is produced by the placenta to maintain uterine function, hCG is no longer needed and the amount levels off and declines by approximately 12- 14 weeks gestation.

Front 48

What are the levels for a positive hCG test?

Back 48

Positive test is >5 mIU/mL in serum or >25 mIU/mL in urine, and level reaches very high values by end of 1st trimester (1st three months)

Front 49

What is human placental lactogen?

Back 49

Human placental lactogen is a single polypeptide chain with similarities in structure to growth hormone.
The hormone helps prepare the mammary glands for lactation.

Front 50

What are some problems in early pregnancy?

Back 50

Difficulty with pregnancies in early stages include ectopic pregnancies or failure to maintain the pregnancy in the uterus, leading to miscarriage.

Front 51

What is an ectopic pregnancy?

Back 51

Ectopic pregnancy is a pregnancy in which the fertilized ovum is unable to implant in the uterus and remains in the fallopian tubes or the ovary. Ectopic pregnancy remains one of the most common causes of maternal death during the first trimester, typically characterized by severe pain and hemorrhage as with clotting disorders a more severe complication that may lead to death.

Front 52

What is the most common cause of ectopic pregnancy?

Back 52

The most common cause of ectopic pregnancy is scarred or obstructed fallopian tubes secondary to sexually transmitted disease or pelvic inflammatory disease

Front 53

How is a patient diagnosed with ectopic pregnancy?

Back 53

Diagnosis of ectopic pregnancy is made through patient history of pain and bleeding, physical exam (showing a pelvic mass), visualization by ultrasound and hCG levels that are abnormally low and with a slow rate of increase.

Front 54

What is the most common cause of miscarriage?

Back 54

The most common cause of miscarriage is an abnormally developing blastocyst or embryo.

Miscarriage can also result from hormonal fluctuations including inadequate levels of progesterone or estrogens, necessary for maintenance of the uterine lining. A sudden drop in progesterone levels will cause the endometrium to slough, evacuating the embryo and causing menstruation to begin.

Front 55

What is a trophoblastic neoplasm?

Back 55

Trophoblastic neoplasm results in a tumor growth, rather than a fetus, in the uterus. There are several types including hydatiform mole, invasive hydatiform mole or choriocarcinoma.

Front 56

What is a Hydatiform mole?

Back 56

Hydatiform mole is a benign growth, which is characterized by abnormal growth of chorionic villi, edema and grape-like clusters of watery sacs in the uterus that are visible by ultrasound.
Invasive hydatiform mole is similar to hydatiform mole but the chorionic villi grow to invade the uterine smooth muscles.

Front 57

What is Choriocarcinoma?

Back 57

Choriocarcinoma is a malignancy in which the chorionic villi invade not only the uterus but spread to surrounding organs. Choriocarcinomas arise from the trophoblast. Quantitative hCG levels are helpful in determining progression of neoplastic disease since levels correlate with the amount of tumor present. A patient with hCG of 400,000 IU/L or higher would be expected to have a poor prognosis even with treatment.

Front 58

What happens to hCG when the patient is pregnant with twins?

Back 58

It doubles

Front 59

Other hormone tests: Progesterone

Back 59

Peak indicates that ovulation has occurred. Used when assessing infertility in women.

Front 60

Other hormone tests: FSH and LH

Back 60

FSH & LH levels are increased after menopause (= 1o gonadal failure)
Also used in assessing infertility in men and women.

Front 61

Other hormone tests: Testosterone and E2

Back 61

Used to assess gonadal function

Front 62

What is hypogonadism?

Back 62

lack of gonadal function
In children, delayed onset of puberty indicates possible hypogonadism
In adults, amenorrhea and  libido, or infertility indicate possible hypogonadism

Front 63

What is primary hypogonadism?

Back 63

Decrease gonadal hormone (E2 or testosterone) and gonadotropins (FSH & LH)
If 1o then chromosome analysis is warranted to rule out Turner's syndrome (XO) in female or Klinefelter's syndrome (XXY) in male

Front 64

What is Secondary hypogonadism?

Back 64

Decreased gonadal hormone (estrogen, testosterone) and decreased gonadotropins

Front 65

What is hypergonadism?

Back 65

Excessive androgen production
precocious puberty in child
no effect in adult
Testicular tumor (1o)
Pituitary tumor (2o)

Front 66

What is Hirsutism?

Back 66

Excessive androgen-sensitive hair growth in women in areas where hair follicles are not normally found