The relationship of sonographic placental grading, biochemical pulmonary maturity and neonatal outcome in pregnancy-induced hypertension.

In a prospective study, the accuracy of placental grade in predicting pulmonary maturity was evaluated in 50 cases of pregnancy-induced hypertension (PIH) between 28 and 41 weeks of gestation. Pulmonary maturity was measured by lecithin/sphingomyelin (L/S) ratio and phosphatidylglycerol (PG) in amniotic fluid and by clinical development of respiratory distress syndrome (RDS) in the neonates. Fifty normotensive healthy primigravidae, who were matched for age and period of gestation, served as control. No difference (p > 0.05) in the placental grading was observed between normotensive and hypertensive pregnancies. The advancement of placental grade was found to be associated with an increase in L/S ratio and PG level in amniotic fluid. A mature placental grade (grade III) identified by real-time sonography corresponded to foetal lung maturity (L/S > or = 2.0, PG > or = 0.36 mg/dl) and absence of RDS in all cases. Hence, in PIH a grade III placenta appeared to be a reliable predictor of foetal lung maturity in the population examined.