Randomized controlled trial investigating the efficacy of oral azithromycin in preventing perinatal infections in pregnant women undergoing labor induction.

Abstract

Objectives: This study evaluates oral azithromycin's effectiveness in reducing intrapartum and puerperal infection rates in term pregnant women undergoing labor induction to guide antibiotic prophylaxis.

Methods: This single-center randomized controlled trial enrolled 472 women with term singleton pregnancies undergoing labor induction. The participants were randomly allocated to receive either 2 g of oral azithromycin (n = 236) or no treatment (n = 236). The primary outcome was the overall perinatal infection rate (which includes both intrapartum and/or puerperal infections). Secondary outcomes included maternal and neonatal complications, mode of delivery, and safety parameters. Results analysis adopted an intention-to-treat approach.

Results: The overall perinatal infection rate did not differ significantly between the azithromycin group (16.1%) and the control group (16.9%) (absolute risk difference [ARD] = -0.85%, relative risk [RR] = 0.950, 95% confidence interval 0.633-1.425; P = 0.804). Similarly, the incidence of neonatal infectious diseases showed no significant difference between the two groups (2.5% vs 5.1%, P = 0.149). Both groups had comparable outcomes in mode of delivery, maternal-neonatal complications (epidural analgesia, postpartum hemorrhage, and pre- and post-delivery antibiotic use), total labor duration, neonatal hypoglycemia, neonatal intensive care unit admission, and neonatal antibiotic administration. Maternal outcomes did not differ significantly between groups, although 3.4% (8/236) of women in the azithromycin group reported gastrointestinal symptoms during labor, with a total adverse event rate of 3.8% (9/236, including one case of dizziness).

Conclusion: The use of an additional 2 g azithromycin provides no additional benefit in reducing the overall risk of maternal infection and perinatal infection in an already intensive antibiotic prophylactic and well-resourced setting.

Clinical trial registration: This study was registered in the Chinese Clinical Trial Registry, registration number ChiCTR2300077629, November 14, 2023 (https://www.chictr.org.cn/showprojEN.html).