Pulmonary hypoplasia and fetal breathing in preterm premature rupture of membranes.

Forty-eight patients with premature rupture of membranes prior to 24 weeks gestation (PPROM) were studied to investigate whether there was any difference in fetal breathing movements in those fetuses that did or did not develop pulmonary hypoplasia. The diagnosis of pulmonary hypoplasia was made on the basis of ultrasound measurement of fetal lung length. A control group of fetuses with intact membranes and normal pregnancies at the same gestation was also studied. The group that developed pulmonary hypoplasia had significantly less breathing movements than those that did not develop pulmonary hypoplasia and controls. This reduction in breathing movements may contribute to the development of pulmonary hypoplasia.