Outcomes of extremely preterm infants exposed to prolonged prelabor rupture of membranes before 24 weeks of gestation

Abstract

Background: Preterm prelabor rupture of membranes before or around the limit of fetal viability is associated with serious maternal and neonatal complications, including chorioamnionitis, extremely preterm birth, and pulmonary hypoplasia.

Objective: This study aimed to describe the contemporary outcomes of extremely preterm infants born after prolonged periviable preterm prelabor rupture of membranes and to identify perinatal factors associated with survival and survival without severe neurodevelopmental impairment.

Study design: Among actively treated infants born alive at <27 weeks' gestational age in centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network from 2012 to 2018, the outcomes of survival and survival without severe neurodevelopmental impairment at 22 to 26 months' corrected age were compared between infants exposed to prolonged (≥120 hours) periviable (<24 weeks' gestational age) preterm prelabor rupture of membranes and unexposed infants born after rupture of membranes ≤18 hours before delivery or at delivery with adjustment for birth gestational age, sex, multiple gestation, antenatal steroids, small for gestational age, insurance, and center. Regression models were used to identify perinatal factors associated with survival and survival without severe neurodevelopmental impairment among the infants exposed to prolonged periviable preterm prelabor rupture of membranes.

Results: The analysis included 609 infants exposed to prolonged periviable preterm prelabor rupture of membranes and 4489 unexposed infants. In the prolonged periviable preterm prelabor rupture of membranes group, 444 of 608 (73%) infants survived and 298 of 533 (56%) infants survived without severe neurodevelopmental impairment. The odds of survival (odds ratio, 0.84; 95% confidence interval, 0.68-1.05) and survival without severe neurodevelopmental impairment (odds ratio, 0.91; 95% confidence interval, 0.75-1.12) were not significantly different between prolonged periviable preterm prelabor rupture of membranes and unexposed groups. The variables associated with higher odds of survival without severe neurodevelopmental impairment were later gestational age at birth (odds ratio, 1.37; 95% confidence interval, 1.13-1.67), later gestational age at preterm prelabor rupture of membranes (odds ratio, 1.44; 95% confidence interval, 1.26-1.63), and female sex (odds ratio, 1.57; 95% confidence interval, 1.06-2.34), whereas small-for-gestational-age infants had lower odds of survival without severe neurodevelopmental impairment (odds ratio, 0.14; 95% confidence interval, 0.04-0.51).

Conclusion: The odds of survival and survival without severe neurodevelopmental impairment among infants exposed to prolonged periviable preterm prelabor rupture of membranes were not significantly different from those of unexposed infants but decreased with earlier gestational age at birth and rupture of membranes.

Keywords: extreme prematurity; neonate; neurodevelopmental outcomes; periviable; preterm prelabor rupture of membranes; pulmonary hypoplasia.