Maternal and neonatal outcomes associated with expanded antibiotic therapy in preterm prelabor rupture of membranes

To compare maternal and neonatal outcomes in women with preterm prelabor rupture of membranes (PPROM) managed expectantly with either ampicillin-erythromycin or an institutional alternative regimen combining ampicillin, ceftriaxone, and clarithromycin.

This was a retrospective historical cohort study at a tertiary referral center in Cali, Colombia, including women with singleton pregnancies and confirmed PPROM between 24⁺⁰ and 34⁺⁶ weeks (January 2019-December 2024). Ampicillin-erythromycin was used from 2019 to 2022, and ampicillin-ceftriaxone-clarithromycin from 2023 to 2024. Primary outcomes included maternal infectious morbidity and early-onset neonatal sepsis. Latency was assessed using the restricted mean time to delivery (RMTD) from Kaplan-Meier curves.

A total of 136 women were included: 64 received ampicillin-erythromycin and 72 received ampicillin-ceftriaxone-clarithromycin. The alternative regimen was associated with lower rates of clinical chorioamnionitis (16.7% vs. 32.8%; P = 0.044), maternal sepsis (1.4% vs. 14.1%; P = 0.006), postpartum endometritis (1.4% vs. 12.5%; P = 0.013), and early-onset neonatal sepsis (46.5% vs. 66.1%; P = 0.039). Latency was numerically longer but did not reach statistical significance (RMTD difference 1.39 days; 95% confidence interval [CI]: -2.40-5.18; P = 0.471).

In expectantly managed PPROM before 35 weeks, ampicillin-ceftriaxone-clarithromycin was independently associated with a reduction in clinical chorioamnionitis after multivariable adjustment. The association with early-onset neonatal sepsis was present in analysis but attenuated after adjustment, and should be interpreted as exploratory. Prospective studies are needed to confirm efficacy, safety, antimicrobial resistance implications, and long-term neonatal outcomes.