Chapter 6: Preconception and antepartum care

Question 1

How much folic acid should a woman trying to become pregnant be taking?

Answer 1

Taking 0.4 mg Folic Acid per day up through first trimester for prevention of NTDs. 4mg daily if prior NTD pregnancy or taking meds that interfere with folate metabolism

Question 2

African Americans should be screened for what genetic disorders?

Answer 2

Sickle, B-Thal/a-Thal.

Question 3

Mediterranean or Southeastern Asian folks should be screened for what genetic disorders?

Answer 3

B-thal, a-thal

Question 4

Ashkenazi Jews should be screened for what genetic disorders?

Answer 4

Tay-Sachs, Canavan disease, Familial dysautonomia, Cystic fribrosis

Question 5

How long should you wait to become pregnant after having a live vaccine?

Answer 5

Avoid conception within a month of receiving a live vaccine like Rubella

Question 6

What general physical exam findings and 3 signs do we note with someone who is pregnant?

Answer 6

a. Softening and enlargement of the pregnant uterus 6 or more weeks after LNMP. 12 weeks uterus is substantially larger and palpable on abdominal exam in lower abdomen.
b. Chadwick sign: Bluish discoloration of the vagina
c. Hegar sign: Softening of the cervix
d. Circumlinear striae on abdominal wall secondary to progesterone and dermal stretching

Question 7

What is quickening and when does it occur?

Answer 7

Quickening: 16-18 weeks, this is the initial feeling of fetal movement (as late as 20 weeks for first time mothers)

Question 8

How should hCG change during pregnancy?

Answer 8

hCG should double every 1.5-2 days

Question 9

What tools can we use to detect fetal heart beat and when are they accurate?

Answer 9

Fetal heart beat at 18-20 weeks with acoustic fetoscope,or with electronic Doppler at 12 weeks.

Question 10

On an initial prenatal visit, what are some labs and tests we want to consider ordering?

Answer 10

Labs: Blood type, D (Rh) Type, Antibody screen, CBC, VDRL/RPR, Urine Cx/Screen, HBsAg, HIV, Chlamydia, Gonorrhea when indicated.

Supplemental: Hgb, PPD, PAP, Cystic fibrosis, HPV, Tay-Sachs/Canavan Disease, Early Diabetes screen, Familial dysautonomia

Question 11

What is Gestational age and how do we calculate it

Answer 11

Gestational age: number of weeks since first day of LMP. Calculate this along with an estimated date of delivery using Naegele’s rule (add 7 days to the first day of the LMP, subtract 3 months, add a year.

Question 12

What else can be added to help assist with calculating gestational age?

Answer 12

US dates overrule LMP/Naegele’s Rule calculations, and can be done 5-6 weeks (Abd US) after first day of LMP (bHCG levels of 5,000 – 6,000. Transvaginal at 3-4 weeks (1,000 – 2,000) as probe is placed in posterior fornix of vagina only a few cm from the uterus.

Question 13

When do we check for gestational HTN?

Answer 13

After 20 weeks, check for gestational HTN

Question 14

What are weight gain recommendations for pregnancy?

Answer 14

Underweight: BMI

Question 15

What is the goal of fundal height measurements?

Answer 15

After 20 weeks, fundus palpable at umbilicus. From 16-18 to about 36 weeks, fundal height in cm equals the week number approximately. After that, fetus moves down to prepare for labor so the number isn’t reliable.

Question 16

What should we be thinking about with uterine palpation during visits?

Answer 16

What’s the baby doing?

95% at term will be cephalic, 3.5% breech

Do Leopold maneuvers

If Breech persists at 36-38 weeks, do external cephalic version

Question 17

What screening do we do during the first trimester?

Answer 17

First trimester: 10-13 weeks: PAPP-A, B-hCG, US for nuchal.

Question 18

What screening do we do during the second trimester?

Answer 18

Second: 15-20 weeks: Triple (maternal serum AFP, estriol, hCG) or Quad (Triple + inhibin)

You can also do first and second at once during second trimester

Question 19

Third Trimester Screening?

Answer 19

Third: Glucose challenge test, GDM (24-28 weeks), GBS (35-37 weeks), and potential re-screening for Rh antigens and HIV

Question 20

How do we assess for growth changes in the fetus?

Answer 20

US for growth changes. If abnormal, consider amniotic fluid issues, macrosomia, hydatiform mole, incorrect dating, abortion, or multiple pregnancies.

Question 21

Fetal Monitoring besides growth restrictions is best done with what tests?

Answer 21

NST
CST
BPP or modified BPP

Question 22

How does an NST work?

Answer 22

Nonstress Test: NST: Measures fetal heart rate, patterns and accelerations, monitored on a transducer for at least 20 minutes while button is pressed with fetal movements

Question 23

How does a CST work?

Answer 23

CST: Whereas the NST evaluates the fetal heart response to fetal activity, the CST measures response of fetal heart rate to stress of uterine activity. Use a tocodynamometer for 20 minutes and use oxytocin if there are no contractions for 10-20 minutes. High false positive results so correlate with other tests appropriately.

Question 24

How does a BPP work?

Answer 24

BPP: Biophysical profile: Use when you have a bad NST. Score of 8-10 is reassuring. 0 points for absent, 2 points for present

1. NST: 0 = bad, 2 = good
2. Fetal breathing movements (At least one or more episodes of fetal rhythmic breathing movements of 30 seconds or more within 30 minutes
3. Fetal movement: Three or more discrete body or limb movements within 30 minutes
4. Fetal tone: One or more episodes of fetal extremity extension with return to flexion, or opening or closing of hand within 30 minutes
5. Amniotic fluid volume: Pocket of amniotic fluid that measures at least 2 cm in two planes perpendicular to each other
   - Decreases when fetus is stressed and shunts blood from kidneys = less pee

Question 25

What’s a modified BPP?

Answer 25

Modified BPP: NST with AFI (fluid at 4 quadrants)

Question 26

What all do we look at to assess if the fetus is maturing properly?

Answer 26

Sequentially, lungs are the last thing to develop, so many of our maturity tests look at lung development.

Surfactant is key.

Question 27

What is surfactant?

Answer 27

Collection of phospholipids that maintain patency of alveolar sacs and can be measured in amniocentesis

Question 28

What two phospholipids do we look at specifically?

Answer 28

Two phospholipids specifically can also be detected, lecithin and sphingomyelin, in an LS ratio, to determine fetal lung maturity

Question 29

What is phosphatidylglycerol and when do we look at it?

Answer 29

Phosphatidylglycerol is a phospholipid present with complete lung maturity present after 35 weeks

Question 30

What happens if we delivery before lung maturity?

Answer 30

Delivery before lung maturity can lead to respiratory distress syndrome (grunting, chest retractions, nasal flaring, hypoxia) that can lead to acidosis and death. Administer surfactant if needed.

Question 31

What is Pica? Why do we care?

Answer 31

Pica, abnormal eating, associated with anemia so watch for this

Question 32

What mineral supplementation is needed during pregnancy?

Answer 32

Except iron, you don’t need to supplement minerals. Vitamins only if diet is not substantial. 27 mg of iron is recommended

Question 33

Are there travel restrictions when pregnant?

Answer 33

Travel up to 36 weeks by air unless with HTN, DM, sickle. After 36, you could give birth, so don’t be in the sky. Move around to prevent DVT/PE

Question 34

What do we worry about with exercise in pregnancy?

Answer 34

Workout during and after pregnancy as long as you don’t have stress such as heart or lung disease, multiple gestations, placenta previa after 26 weeks, ruptured membranes, preeclampsia, GDM. Limit supine exercises after first trimester to minimize circulatory changes brought on by IVC pressure. Avoid saunas and extreme heat due to potential harm of hyperthermia on fetus.

Question 35

Other than meds, what do we do as far as other teratogens?

Answer 35

Other than meds, there are a ton. Tell patients to visit Organization of Teratology Information Services to find out more (www.otispregnancy.org) or use yourself if patient is curious

Question 36

How does the FDA classify meds as teratogens?

Answer 36

A: Controlled human studies demonstrate no risk in any trimester

B: Animal studies show no fetal harm but no pregnant lady studies, OR, abnormal animal studies with normal pregnant lady research

C: Animal studies with adverse effect with no adequate human studies OR No animal or human studies performed

D: Good human studies show BAD results to fetus. HOWEVER, benefits may outweigh risks

X: Don’t use, it’s real bad. Absolutely contraindicated if pregnant or want to become pregnant.

Question 37

Side effects on baby with tetracycline use

Answer 37

Tetracyclines: Yellow brown baby teeth with doxycycline and minocycline

Question 38

Side effct of sulfonamides on baby

Answer 38

Sulfonamides: Hyperbilirubinemia due to displacement of bilirubin from protein binding sites. Avoid near delivery date

Question 39

Warfarin vs. Heparin in pregnancy

Answer 39

Warfarin: Crosses placenta REAL easy. Nasal and midface hypoplasia with stippled vertebral and femoral epiphyses is exposed in weeks 6-9. Late exposure associated with hemorrhage related fetal abnormalities like hydrocephalus

Heparin/low molecular weight heparin: Anticoag of choice for use in pregnancy because large polar molecules don’t cross placenta.

Question 40

Mercury during pregnancy

Answer 40

Mercury: You can consume fish low in mercury (shrimp, canned light tuna, salmon, Pollock, catfish), up to 12 ounces per week. Avoid large fish (that accumulate mercury from eating smaller fish) like Large tuna, shark, king mackerel.

Question 41

CT during pregnancy?

Answer 41

Radiation: Keep is below 5 rads. One CT is about 3rads for pelvis, 1 rad for head.

Question 42

Alcohol during pregnancy

Answer 42

Alcohol: Exposure is at its worst in first trimester. No established safe levels, and dose responses are linked to mental retardation, developmental delays and abnormalities.

FAS: Growth restriction, facial abnormalities (shortened palpebral fissure, low set ears, midfacial hypoplasia, smooth philtrum, thin upper lip), CNS dysfunction (microcephaly, mental retardation, behavioral disorders like attention deficit disorders)

Question 43

What the hell is round ligament pain?

Answer 43

Round ligament pain: RLQ pain that looks like appendicitis. Just stretching and spasm of round ligament. Limit quick movements. Analgesics not indicated.

Question 44

What do we do about the N/V seen during pregnancy?

Answer 44

Nausea/Vomiting: First trimester very bad for morning sickness. Edit diet and lifestyle changes. If serious, use antihistamine H1-receptor blockers and phenothiazines. Most severe form is hyperemesis gravidum which occurs in 2% of pregnancies. Fluid, electrolytes and hospitalization may be needed

Question 45

What do we do about the headaches and edema seen during pregnancy?

Answer 45

Headaches: Unknown why. Give Acetaminophen, and test further if they persist.

Edema: Could be hypertension but could also be normal. Be smart about treatment.