Is Preterm Premature Rupture of Membranes Latency Influenced by Single Versus Multiple Agent Antibiotic Prophylaxis in Group B Streptococcus Positive Women Delivering Preterm?

OBJECTIVE: To evaluate the influence of antibiotic regimen on the duration of latency (time from preterm pre-labour rupture of membranes [PPROM] to delivery) and significant infectious neonatal morbidity from rupture of membranes to delivery < 37 weeks' gestational age in women known to be group B Streptococcus (GBS) positive.

METHODS: We obtained data from the Nova Scotia Atlee Perinatal Database. In a retrospective, cohort, population-based study, we included pregnancies complicated by PPROM but excluded pregnancies in this group requiring immediate delivery. The cohort was categorized by antibiotic regimen (single vs. multiple agents) and we compared latency and adverse neonatal outcomes according to antibiotic regimen used. Summary characteristics were compared using chi-square analysis with significance < 0.05. Logistic regression was used to estimate adjusted odds ratios, 95% confidence intervals, and mean differences for all outcomes and to account for confounding variables.

RESULTS: From 1988 to 2011, the potential study population was 119 158 pregnancies. In total, 3435 deliveries were identified to be PPROM (3%). Of these, 303 mother-baby pairs (9%) were known to be GBS positive by urine or swab culture. Adjusted comparisons of latency and neonatal sepsis showed no difference according to antibiotic regimen (P > 0.05).

CONCLUSION: The 2013 SOGC guideline on GBS prophylaxis recommends antibiotic therapy in women with PPROM for both latency and prevention of GBS-related neonatal sepsis. This clinically relevant evaluation in a select preterm group demonstrated that type of antibiotic regimen did not influence either latency with PPROM and GBS positive culture or rates of neonatal sepsis. Ongoing evaluation of serious neonatal outcomes is essential in view of this new recommendation.