Objective: Our purpose was to determine whether congenital diaphragmatic hernia is associated with abnormalities of fetal lung maturation.
Study design: We measured surfactant protein A and saturated phosphatidylcholine in amniotic fluid from 19 pregnancies with a prenatal diagnosis of congenital diaphragmatic hernia (gestational age 16 to 40 weeks) and 48 control pregnancies (gestational age 16 to 39 weeks). Results were compared by analysis of covariance.
Results: Beyond 34 weeks of gestation there was a progressive rise in amniotic fluid surfactant protein A and saturated phosphatidylcholine in control pregnancies, whereas in most fetuses with prenatal diagnosis of congenital diaphragmatic hernia these values remained low (p < 0.01). Amniotic fluid surfactant protein A was lower in fetuses with congenital diaphragmatic hernia who died or required extracorporeal membrane oxygenation than in survivors treated with conventional management (4.9 +/- 2.9 vs 16.8 +/- 5.7 micrograms/ml surfactant protein A, respectively, p < 0.05 by Mann-Whitney U test).
Conclusions: There are decreased surfactant components in amniotic fluid in many pregnancies complicated by congenital diaphragmatic hernia, which may reflect fetal lung immaturity or hypoplasia.