Latency to delivery and incidence of adverse obstetric and perinatal outcomes in preterm premature rupture of membranes before 32 weeks

Purpose: The aim of this study was to evaluate the average latency to delivery, obstetric outcomes and neonatal survival in pregnancies complicated by preterm premature rupture of membranes (PPROM) before 32 weeks. Methods: A retrospective study was conducted on pregnant women admitted for PPROM before 32 weeks. Patients were categorized into three groups based on gestational age (GA) at PPROM (< 24, 24 to 28, 28 to 32 weeks). Latency to delivery, obstetric outcomes and neonatal survival were analyzed. Results:  86 women who had PPROM before 32 weeks were identified. The mean GA at PPROM was 26.1 weeks and the median latency to delivery was 16 days (IQR 4, 27). The median latency to delivery was 22 days for previable PPROM, 11 days for PPROM between 24 and 28 weeks, and 16 days for PPROM between 28 and 32 weeks (p = 0.29). All cases of placental abruption (7/86, 8%) and cord prolapse (6/86, 7%) occurred in women with PPROM before 28 weeks. In 44% of PPROM, placental histology demonstrated chorionamnionitis. Neonatal survival at discharge was significantly lower in previable PPROM (< 24 weeks) compared to PPROM at 24-26 weeks (58% vs 92%, p = 0.04), and it reached 100% in cases of PPROM after 28 weeks. Conclusion: In PPROM occurring before 32 weeks the median latency to delivery ranged between 11 and 22 days. Neonatal survival improves with higher GA at PPROM, and it increases by more than 33% when PPROM occurs after 24 weeks of gestation. These data may be valuable for patient counselling.