Pregnancy, Labor & Delivery

Q1: What happens to GI motility and gastric acid secretion during pregnancy?.

A1: GI motility decreases and gastric acid secretion decreases → can affect absorption.

Q2: How does nausea and vomiting affect absorption in pregnancy?

A2: It can reduce bioavailability due to poor intake and vomiting.

Q3: What happens to maternal blood volume and total body water during pregnancy?

A3: Blood volume ↑ by 30-50%; TBW ↑ → increases Vd for hydrophilic drugs.

Q4: What happens to body fat and albumin concentration during pregnancy?

A4: Body fat ↑ → ↑ Vd of fat-soluble drugs; Albumin ↓ → ↑ Vd of highly protein-bound drugs.

Q5: How does renal elimination change in pregnancy?

A5: Renal blood flow ↑ 25-50%; GFR ↑ 50% by 2nd trimester → renally cleared drugs (e.g., β-lactams) may need ↑ dosing by 20-65%.

Q6: What are the key hepatic enzyme changes in pregnancy?

A6: CYP3A4, CYP2D6 ↑ → faster clearance; CYP1A2 ↓ → slower clearance.\

Q7: How does plasma albumin change affect drug distribution?

A7: Less binding → more free drug → faster clearance → total drug level may decrease but unbound stays stable.

Q8: Define teratogen.

A8: A drug or agent that can produce abnormal fetal development.

Q9: When is the embryo most susceptible to teratogens?

A9: During organogenesis — weeks 4-10.

Q10: Which meds are classic teratogens?

A10: Retinoids, thalidomide, warfarin, lithium, chemotherapy, some antiseizure meds.

Q11: What is the “all-or-none” period?

A11: First 4 weeks: exposure either causes miscarriage or no effect.

Q12: When are NSAIDs and tetracyclines risky?

A12: 2nd & 3rd trimesters — can affect fetal organs.

Q13: Name two trustworthy resources to assess drug safety in pregnancy.

A13: Briggs’ Drugs in Pregnancy and Lactation; MotherToBaby Fact Sheets.

Q14: What replaced the old FDA pregnancy risk categories?

A14: Pregnancy & Lactation Labeling Rule — more narrative risk summaries instead of A/B/C/D/X.

Q15: What supplements should every pregnant person take?

A15: Folic acid 0.4 mg/day (↑ if high risk for NTD); multivitamin with iron (27 mg) & calcium (1000–1300 mg).

Q16: What vaccines are safe during pregnancy?

A16: Inactivated flu vaccine; Tdap at 27–36 weeks. NO live vaccines.

Q17: What are signs/symptoms of pregnancy?

A17: Cessation of menses, breast changes, fatigue, nausea/vomiting, increased urination.

Q18: What is gestational diabetes & when is it screened?

A18: Glucose intolerance diagnosed at 24–28 weeks; screen with 50g OGTT.

Q19: Name risks of uncontrolled GDM.

A19: Macrosomia, neonatal hypoglycemia, congenital defects, future T2DM for parent & child.

Q20: Name risk factors for GDM.

A20: BMI ≥ 25, age >35, prior GDM, large prior baby (>4 kg), PCOS, family hx diabetes.

Q21: What is first-line tx for GDM?

A21: Lifestyle & diet; insulin if needed; metformin or glyburide as alternatives.

Q22: How is preeclampsia defined?

A22: BP ≥140/90 + proteinuria (>300 mg/24h) OR signs of organ damage.

Q23: What is eclampsia?

A23: Preeclampsia with seizures → medical emergency.

Q24: Drugs for acute severe HTN in pregnancy?

A24: IV labetalol, hydralazine, or nifedipine. Avoid ACE-I, ARBs.

Q25: How do you prevent eclampsia seizures?

A25: Magnesium sulfate IV during labor & postpartum.

Q26: What is HELLP syndrome?

A26: Hemolysis, Elevated Liver enzymes, Low Platelets — variation of preeclampsia.

Q27: What defines postpartum hemorrhage?

A27: Blood loss >1000 mL or signs of hypovolemia within 24 hrs postpartum.

Q28: First-line and second-line uterotonics for postpartum hemorrhage?

A28: Oxytocin → if needed, methylergonovine, carboprost, or misoprostol. Tranexamic acid can help too.

Q29: What are the baby blues vs postpartum depression?

A29: Blues: mild, self-limiting; PPD: more severe, needs treatment → sertraline, paroxetine, fluoxetine, nortriptyline.

Q30: What defines preterm labor?

A30: Contractions + cervical change <37 weeks.

Q31: What is tocolytic therapy for?

A31: Delay labor 48h–1 week to give corticosteroids & magnesium time to work.

Q32: Name 4 classes of tocolytics.

A32: β-agonists (terbutaline), calcium channel blockers (nifedipine), NSAIDs (indomethacin), magnesium sulfate.

Q33: Why give antenatal corticosteroids?

A33: Accelerate fetal lung maturity → betamethasone or dexamethasone.

Q34: What is GBS prophylaxis?

A34: IV ampicillin q4h if GBS+ → prevent neonatal infection.