Premature labor and premature rupture of the membranes

The effects of prolonged rupture of membranes upon the outcome of the mother and the fetus remain a problem in obstetrics. In an attempt to correlate the time interval between premature rupture of the membranes (PROM) and the onset of labor prior to term and maternal and perinätal outcome, a retrospective study was done in patients admitted to the Duke University Medical Center during the 5 year interval 1971 to 1975. Of these patients, 184 had premature labor prior to the rupture of membranes and 151 had PROM. A total of 335 pregnant patients who bore infants weighing from 1,000 to 2,500 grams were studied. Only infants of appropriate weight for their gestational age at birth and without apparent fetal malformations were included in the study. The time interval between rupture of membranes and onset of labor and delivery ranged from 0 hours to 4 weeks. All the patients were divided into three groups according to birth weight. For each group with PROM, the length of time of rupture of membranes prior to labor was compared with the development of neonatal respiratory distress syndrome (RDS) and maternal and neonatal infections. Infants from mothers with premature labor only were used as a reference group. Statistically, the data demonstrated a decrease in RDS in infants weighing from 1,000 to 1,500 grams with an increase in duration of rupture of membranes. This incidence of RDS was not altered when birth weight was above 1,500 grams. The development of fetal pulmonary maturity and the effect of time in relationship to the development of maternal and fetal infections and a possible time for delivery following PROM are discussed.