Hy Embryology 05 Part 2

Front 1

Describe Human Chorionic Gonadotropin (hCG)

Back 1

A glycoprotein that stimulates the production of progesterone by the corpus luteum

Front 2

Describe Human Placental Lactogen (hPL)

Back 2

-A protein hormone that induces lipolysis, elevating free fatty acid levels in the mother
-It is considered to be the "growth hormone" of the fetus

Front 3

What is the "growth hormone" of the fetus?

Back 3

Human Placental Lactogen (hPL)

Front 4

Describe Estrone, Estradiol, and Estriol

Back 4

Steroid hormone produced by the placenta, but little is known about their specific functions in either the mother or the fetus

Front 5

Which is most potent: Estrone, Estradiol, and Estriol

Back 5

Estradiol

Front 6

Describe progesterone

Back 6

A steroid hormone that maintains the endometrium during pregnancy, is used by the fetal adrenal cortex as a precursor for glucocorticoid and mineralocorticoid synthesis, and is used by the fetal testes as a precursor for testosterone synthesis

Front 7

What hormrone maintains the endometrium during pregnancy?

Back 7

Progesterone

Front 8

What hormone is used by the fetal adrenal cortex as a precursor for glucocorticoid and mineralocorticoid synthesis?

Back 8

Progesterone

Front 9

What hormone is used by the fetal testes as a precursor for testosterone synthesis?

Back 9

Progesterone

Front 10

Describe the placental membrane in early pregnancy

Back 10

1. Consists of the syncytiotrophoblast, cytotrophoblast (Langerhans cells), connective tissue and the endothelium of the fetal capillaries.
2. Hofbauer cells are found in the connective tissue and are more likely macrophages

Front 11

Describe Hofbauer cells

Back 11

1. Found in the connective tissue in early pregnancy
2. Likely to be macrophages

Front 12

Describe the placental membrane in late pregnancy

Back 12

The cytotrophoblast degenerates and the connective tissue is displaced by the growth of fetal capillaries, leaving the syncytiotrophoblast and the fetal capillary endothelium

Front 13

Describe the function of the placental membrane

Back 13

1. Seperates maternal blood from fetal blood
2. A wide variety substances freely cross the placental membrane

Front 14

What beneficial molecules can cross the placenetal membrane?

Back 14

-O2
-CO2
-Glucose
-L-form amino acids
-Free fatty acids
-Vitamins
-Water
-Urea
-Uric acid
-Bilirubin

Front 15

What beneficial ions can cross the placental membrane?

Back 15

-Na+
-K+
-Ca2+
-Cl-
-I-
-PO4 2-

Front 16

What types of beneficial cells can cross the placental membrane?

Back 16

Fetal and maternal RBCs

Front 17

What types of immune components can cross the placental membrane?

Back 17

IgG, IgA

Front 18

What beneficial proteins/hormones can cross the placental membrane?

Back 18

-Maternal serum proteins
-Alpha-fetoprotein
-Transferrin-Fe2+ complex
-Low-density lipoprotein
-Prolactin
-Steroid hormones (unconjugated)

Front 19

What categories of harmful substances can cross the placental membrane?

Back 19

-Virus
-Category X drugs (absolute contraindication in pregnancy)
-Category D drugs (definite evidence of risk to fetus)
-Others

Front 20

What important harmful substances can cross the placental membrane and dont fall into the categories of viruses, category X drugs, and category D drugs?

Back 20

-Carbon monoxide
-Organic mercury, lead, polychlorinated biphenyls (PCBs), potassium iodide
-Cocain, heroin
-Toxoplasma gondii, Treponema palladium, Listeria monocytogenes
-Rubella virus vaccine
-Anti-Rh antibodies

Front 21

What important substances do not cross the placental membrane?

Back 21

-Maternally derived cholesterol, triglycerides, and phospholipids
-Protein hormones (eg, insulin)
-Drugs (eg, succinylcholine, curare, heparin, methyldopa, drugs similar to amino acids)
-IgD, IgE, IgM
-Bacteria in general

Front 22

Describe the cause Erythroblastosis Fetalis

Back 22

1. If the mother is Rh-negative and the fetus is Rh-positive, the mother will produce Rh antibodies
2. This does not affect the first pregnancy
3. In the second pregnancy with a Rh-positive fetus, a hemolyic condiction or RBCs occurs known as Rh-hemolytic disease of newborn (eryhthroblastosis fetalis)

Front 23

Describe Erythroblastosis Fetalis

Back 23

1. From having an Rh- mother and an Rh+ fetus
2. There is destruction of fetal RBCs
3. Leads to the release of large amounts of unconjugated bilirubin
4. This can lead to fetal brain damage (kernicterus) from the pathological deposition of bilirubin in hte basal ganglia

Front 24

What is the treatment for newborns with physiological jaundice?

Back 24

UV light

Front 25

Describe Severe hemolytic disease

Back 25

1. Fetus is severely anemia
2. Fetus demonstrates total body edema (ie hydrops fetalis)
3. May lead to death

Front 26

What is the treatment for severe hemolytic disease?

Back 26

Intrauterine transfusion

Front 27

Describe RhoGAM

Back 27

1. Rh0(D) immmune globulin
2. A human IgG preparation that contains antibodies against Rh factor
3. Prevents a maternal antibody response to Rh+ ceklls tha tmay enter the maternal bloodstead of an Rh- mother
4. Adminstered to Rh- mothers during the third trimester and within 72 hours after birth of an Rh+ baby to prevent erythroblastosis fetalis during subsequent pregnancies

Front 28

When is RhoGAM administered?

Back 28

Adminstered to Rh- mothers during the third trimester and within 72 hours after birth of an Rh+ baby to prevent erythroblastosis fetalis during subsequent pregnancies

Front 29

Describe amniotic fluid

Back 29

A maternally derived water that contains: electrolytes, carbohydrates, amino acids, lipids, proteins (hormones, enzymes, alpha-fetoprotein), urea, creatinine, lactate, pyruvate, desquamated fetal cells, fetal urine, fetal feces (meconium), and fetal lung liquid.

Front 30

Describe the importance of fetal lung liquid

Back 30

Useful for lecithin/sphingomyelin [L/S] ratio measurement for lung maturity

Front 31

Describe the production of amniotic fluid

Back 31

Constantly produced during pregnancy by:
a. Direct transfer from maternal ciruclation in response to osmotic and hydrostatic forces
b. Excretion of fetal urine by the kidneys into the amniotic sac

Front 32

What is the result of fetal kidney defects (ie, bilateral kidney agenesis) on the fetus?

Back 32

Oligohydraminios

Front 33

Describe the resorption of amniotic fluid

Back 33

Constant resorbed during pregnancy by the following sequence:
a. Fetus swallow amniotic fluid
b. Amniotic fluid is absorbed into fetal blood thrihg the GI tract
c. Excess amniotic fluid is removed via the lplacenta and passed into maternal blood

Front 34

What is the result of fetal swallowing defects (eg, esophageal atresia)?

Back 34

Polyhydramnios

Front 35

What is the result of fetal absorption defects (eg, duodenal atresia)?

Back 35

Polyhydramnios

Front 36

Describe the amount of amniotic fluid in pregnancy

Back 36

1. Gradually increased during pregnancy from 50mL at week 12 to 1000mL at term
2. Rate of water exchange within the amniotic sac at term is 400-500 mL/hr, with net flow of 125-200 mL/hr moving from the amniotic fluid into the maternal blood
3. Near-term fetus excretes about 500mL of urine daily, which is mostly water because the placenta exchanges metabolic wasts
4. Fetus swallos ~400mL of amniotic fluid daily

Front 37

Describe Oligohydramnios

Back 37

1. Occurs when there is a low amount of amniotic fluid (<400 mL in late pregnancy)
2. May be associated with the inability of the fetus to excrete urine into the amniotic sac due to renal agenesis
3. Results in many fetal deformities (Potter syndrome) and hypoplastic lungss due to increased pressure on the fetal thorax

Front 38

Describe Polyhydramnios

Back 38

1. Occurs when there is a high amount of amniotic fluid (>2000 mL in late pregnancy)
2. May be associated with the inability of the fetus to swallow due to anencephaly, tracheoesophageal fistula, or esophageal atresia
3. Commonly associagted with maternal diabetes

Front 39

Describe alpha-fetoprotein

Back 39

1. "Fetal albumin"
2. Produced by fetal hepatocytes
3. Routinely assayed in amniotic fluid and maternal serum between weeks 14 and 18 of gestation
4. AFP levels change with gestational age
5. Elevated AFP levels are associated with neural tube defects (eg spina bifida or anencephaly), omphalocele (allows fetal serum to leak into the amniotic fluid), and esophageal and duodenal atresia (which interfere with fetal swallowing)
6. Reduced AFP levels are associated with Down syndrome

Front 40

What are reduced AFP levels associated with?

Back 40

Down syndrome

Front 41

What are elevated AFP levels associated with?

Back 41

-Neural tube defects (eg spina bifida or anencephaly)
-Omphalocele (allows fetal serum to leak into the amniotic fluid)
-Esophageal and duodenal atresia (which interfere with fetal swallowing)

Front 42

Describe premature rupture of the amniochorionic membrane

Back 42

1. Most common cause of premature labor and oligohydramnios
2. Commonly referred to as "breaking of the water bag"

Front 43

What is the most common cause of premature labor and oligohydramnios?

Back 43

Premature rupture of the amniochorionic membrane

Front 44

Describe amniotic band syndrome

Back 44

Occurs when bands of amniotic membrane encircle and constrict parts of the fetus, causing limp amputations and craniofacial anomalies