Azithromycin as Macrolide of Choice in Patients with Preterm Premature Rupture of Membranes in Expectant Management: A Retrospective Study
Abstract Background: Preterm premature rupture of amniotic membranes (PPROM) is responsible for about 30% of premature births, being associated with great neonatal morbidity and mortality. The use of antibiotics in expectant management seems to increase the latency period between PPROM and birth, as well as improving maternal and neonatal outcomes. However, short and long term benefits, and the ideal antibiotics regimen remains controversial. Objective: This study seeks to demonstrate that the use of antibiotics, with azithromycin as macrolide of choice, in expectant management reduces the birth rate in the first 48 hours after PPROM, increasing the latency period between PPROM and birth. Methods: Observational, retrospective cohort study in pregnant women with PPROM treated conservatively at the Hospital de Clínicas de Porto Alegre (HCPA), from January 2012 to December 2019. For the group that used antibiotics, the scheme was Azithromycin and Ampicillin for 48 hours, followed by Amoxicillin for 5 days, completing 7 days of treatment. Qualitative data was analyzed by Fisher exact test, and time to event analysis using Kaplan Meier estimator were used to evaluate latency to birth and Cox regression to estimate Hazard Rate. Results: 145 participants, of which 107 did not use antibiotics (group 1) and 38 used antibiotics (group 2). The 48-hour birth rate was significantly lower in the antibiotics group (33.6% in group 1 vs. 16% in group 2, p=0.04). The birth rate on patients presenting outcomes before 15 days presented a significant reduction (HR 0.6 [95% ICI 0.39 - 0.92]), as well median time to birth as seen in Kaplan Meier estimator by log-rank test. Conclusion: The use of this antibiotics regimen, with azithromicyn as macrolide of choice, reduced the birth rate in the first 48 hours, with potential clinical benefits due to the increase in the pharmacological window for corticosteroid action, among others, and increased median time to birth in first 15 days between PPROM and birth.