Asthma USMLE Step 1 Practice Question
A 29-year-old pregnant woman at 30 weeks gestation presents with preterm labor. Vital signs show BP 138/88 mmHg, HR 102/min, RR 18/min, temp 37.2°C. Amniocentesis is performed to assess fetal lung maturity. Laboratory analysis reveals phosphatidylglycerol present in amniotic fluid and lecithin-to-sphingomyelin ratio of 2.5:1. She denies maternal fever or chorioamnionitis. Which finding best indicates adequate fetal surfactant production and lower neonatal respiratory distress syndrome risk?
Answer choices
- AIncreased fetal insulin concentration
- BHigh phosphatidylglycerol deficiency
- CLow lamellar body count
- DLecithin to sphingomyelin ratio greater than 2Correct answer
- ELow lecithin to sphingomyelin ratio
- FPresence of meconium in amniotic fluid
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