Antibiotic administration after previable preterm prelabor rupture of membranes is associated with prolonged latency.

INTRODUCTION: While antibiotics have been shown to increase the interval to delivery between rupture of membranes and delivery (latency) and improve neonatal outcomes after viable preterm prelabor rupture of membranes (PPROM), this has not been well investigated in the previable PPROM population. We aimed to investigate the association between antenatal antibiotics and latency following previable PPROM. Secondarily, we examined various maternal and neonatal outcomes. We hypothesized that the administration of antibiotics would prolong latency in pregnancies with previable PPROM. METHODS: Single-center retrospective cohort study that included pregnancies diagnosed with previable PPROM between 140/7 and 216/7 and delivered between 2012 and 2024. Administration of antibiotics at any time after membrane rupture to prolong latency was the exposure of interest. Chi-squared tests were performed for categorical variables and the Wilcoxon rank-sum test for numerical variables. Statistical significance was defined as p < 0.05. Multivariable linear regression was performed for the primary outcome, including gestational age at rupture of membranes as a covariate. RESULTS: After controlling for estimated gestational age at rupture of membranes, receipt of antibiotics after previable PPROM was associated with a 14.7-day increase in latency (SE = 6.86, p = 0.034). Antibiotics were associated with a later gestational age at delivery (25.07 vs. 20.31 weeks' gestation) and delivery at or beyond 220/7 (80.95% vs. 15.62%). Administration of antibiotics was associated with lower rates of intrauterine fetal demise (IUFD; 20.63% vs. 65.62%, p < 0.001) and higher rates of neonatal survival to discharge (49.21% vs. 6.25%, p < 0.031). CONCLUSION: Receipt of latency antibiotics after previable PPROM was associated with prolonged latency in both singleton and multiple gestation pregnancies. Those exposed to antibiotics had more deliveries at or beyond 22 0/7 weeks, higher neonatal survival-to-discharge rates, and fewer IUFDs. These findings highlight the potential benefit of latency antibiotics in extending pregnancy duration and improving neonatal outcomes following previable PPROM, supporting their consideration in expectant management and the necessity for larger prospective studies.