Pregnancy and Amniotic Fluid

Question 1

Four functions of the placenta

Answer 1

1. keeps maternal and fetal circulation systems separate
2. Nourishes the fetus
3. Eliminates fetal waste
4. Produces hormones vital to pregnancy

Question 2

Protein that stimulates the ovary to produce progesterone in order to protect the pregnancy

Answer 2

Human Chorionic Gonadotropin

Question 3

Protein hormone that has potent growth and lactogenic properties

Answer 3

Placental lactogen

Question 4

These steroid hormones ensure appropriate development of endometrium, uterine growth, adequate uterine blood supply and preparation of the uterus for labor

Answer 4

Estrogens (estradiol, estriol, esterone) and progesterone

Question 5

Two functions of amniotic fluid

Answer 5

1. Cushions baby against possible injury

2. Helps maintain a constant temperature

Question 6

How many days after conception can hCG can detected in the serum?

Answer 6

B/w 8 and 11 days

Question 7

When does normal doubling time of hCG in early pregnancy occur?

Answer 7

About two days in early pregnancy

Question 8

When do hCG levels peak in a normal pregnancy?

Answer 8

Near the end of the first trimester

Question 9

Describe hCG levels and its doubling time in an ectopic pregnancy

Answer 9

hCG concentration is less in ectopic pregnancies and the doubling time is nearly always greater than 2 days

Question 10

Serum ____ concentrations are often low in mothers w/ abnormal pregnancies

Answer 10

Progesterone

Question 11

Symptoms of pre-eclampsia

Answer 11

Hypertension, proteinuria, and edema

Question 12

Symptoms of eclampsia

Answer 12

Convulsions, rapid and sustained rise in blood pressure, DIC, and intravascular deposition of fibrin w/ subsequent end-organ damage

Question 13

What does HELLP stand for?

Answer 13

Hemolysis, Elevated Liver enzymes, Low Platelet counts

Question 14

Symptoms of HELLP syndrome

Answer 14

Thrombocytopenia, DIC, epigastric pain, malaise, nausea, vomiting, headache, LD/ALT/AST elevated; treatment is delivery

Question 15

Chromosomal abnormality present in Down Syndrome

Answer 15

3 copies of c’some 21 (Trisomy 21)

Question 16

Chromosomal abnormality in Edward’s syndrome

Answer 16

Extra copy of c’some 18 (Trisomy 18)

Question 17

Four tests in the “quad marker screen”

Answer 17

Alpha-Fetoprotein, hCG, unconjugated estriol (E3), and dimeric inhibin A (InA)

Question 18

Relative estriol, hCG, AFP, and dimeric inhibin A quad marker results associated w/ Down Syndrome

Answer 18

Estriol: ~25% lower
hCG: 2x higher
AFP: ~25% lower
Inhibin A: lower

Question 19

Relative estriol, hCG, and AFP quad marker results in Trisomy 18

Answer 19

All are lower

Question 20

Anomaly detected via the detection of increased maternal serum AFP

• Mean AFP = 1.00
• Mean AFP = 3-4
• Mean AFP = 4-7

Answer 20

Neural tube defects

• Mean AFP of 1.00 → unaffected fetus
• Mean AFP of 3-4 → open spina bifida
• Mean AFP of 4-7 → anencephaly

Question 21

Effect of surfactant in the lungs in fetal lung prematurity

Answer 21

Surfactant permits gaseous exchange; lack of surfactant produces neonatal respiratory distress syndrome (RDS)

Question 22

Reduces surface tension in teh alveoli of the lungs

Answer 22

Surfactant

Question 23

W/o surfactant at the alveolar lining-air interface what happens to alveoli?

Answer 23

The alveoli would collapse w/ each inspiration before oxygen/CO2 exchange can occur

Question 24

Two screening tests for fetal lung maturity

Answer 24

1. Lecithin/Sphingomyelin (L/S) ratio
2. Phosphatoidylglycerol (PG) and phosphatidylinositol (PI)
3. Foam stability index
4. Lamellar body count

Question 25

Two major surfactants in the human lung

Answer 25

Phospholipids: lecithin (L) and phosphatidylglycerol (PG)

Question 26

Where are lecithin and PG stored?

Answer 26

In lamellar bodies

Question 27

Risk of newborns that will have RDS according to FLM test

Answer 27

If the amniotic fluid L/S ratio is <2%, 20-25% of newborns will have RDS

Question 28

These are about the same size as platelets and can be counted using standard hematology analyzer

Answer 28

Lamellar bodies

Question 29

A lamellar body count of > ____/mL in amniotic fluid is considered mature

Answer 29

60,000

Question 30

This test is an indirect measurement of the bilirubin concentration in the amniotic fluid where the bilirubin has a max absorbance at 450nm; used as a marker of the severity of fetal hemolysis (HDN)

Answer 30

Delta A450 test

Question 31

Low fluid volume in intrauterine growth retardation and anomalies of the fetal urinary tract

Answer 31

Oligohydramnios

Question 32

High fluid volume in maternal diabetes mellitus, multifetal pregnancy, anencephaly, or spina bifida

Answer 32

Polyhydramnios

Question 33

3 amniotic fluid tests used to assess fetal distress

Answer 33

1. bilirubin spectral scan (Liley Plot) 2. AFP 3. DNA analysis for chromsomal abnormalities

Question 34

What is the significance of an abnormal Liley Plot and what does it look like?

Answer 34

There is a sharp peak at 450nm which indicates bilirubin is in the amniotic fluid; informs us how severe HDN is

Question 35

Function of the AFP amniotic fluid test

Answer 35

To assess neural tube disorders (e.g., spina bifida, anencephaly)

Question 36

An L/S ratio of > ___ together w/ the presence of PG may suggest mature fetal lung development

Answer 36

2.0

Question 37

Performed by mixing equal volumes of amniotic fluid w/ ethanol, followed by vigorous shaking. If foam is produced, adequate surfactants are present

Answer 37

The shake test/foam stability test

Question 38

An FSI ≥ ____ correlates w/ fetal pulmonary maturity and is analogous to an L/S ratio of 2.0

Answer 38

0.48

Question 39

Membrane that covers the embryo and fills w/ amniotic fluid creating the amniotic sac

Answer 39

Amnion

Question 40

Membrane that exists during pregnancy b/w developing fetus and mother

Answer 40

Chorion

Question 41

Membrane enclosing the fetus; afterbirth; plexus in the ventricles of the brain where CSF is produced

Answer 41

Choroid plexus

Question 42

Protein produced by fetal cells, found at the interface of hte chorion and decidua; adhesive that binds the fetal sac to the uterine lining

Answer 42

Fetal fibronectin