Lethal lung hypoplasia in infants after prolonged rupture of membranes.

A retrospective study to detect the frequency of lethal lung hypoplasia in 48 cases with prolonged rupture of membranes (greater than 7 days) before 34 weeks' gestation was made. Fourteen infants died (29%), but only four deaths (8.3%) were due to lung hypoplasia. Three infants with lung hypoplasia had their membranes ruptured before 20 weeks' gestation and showed echoscopically a persistent oligohydramnios, as did the one with rupture at 26 weeks. Neither the duration of rupture of membranes nor the gestational age at the time of rupture showed any influence on the occurrence of lung hypoplasia. The rupture of membranes before 20 weeks' gestational age with resulting persistent oligohydramnios will certainly lead to lung hypoplasia.