Azithromycin Prophylaxis for PRElabor CEsarean DElivery Trial

This is a phase-III multi-center double-blind randomized controlled trial of 8,000 individuals undergoing a scheduled or prelabor cesarean delivery who are randomized to either azithromycin prophylaxis or to placebo. All participants will receive standard of care preoperative antibiotics. The primary objective is to evaluate in patients undergoing scheduled/prelabor cesarean if pre-incision adjunctive azithromycin prophylaxis reduces the risk of post-cesarean infections compared with placebo. Secondary objectives include 1) to assess the perinatal and maternal safety of pre-incision adjunctive azithromycin, 2) to evaluate whether adjunctive azithromycin prophylaxis reduces maternal and neonatal resource use outcomes compared with placebo, and 3) to evaluate whether adjunctive azithromycin influences maternal and neonatal infection with resistant organisms compared with placebo. Individuals will be randomized prior to the start of the cesarean to either 500mg of intravenous azithromycin or to placebo (normal saline). Maternal blood and cord blood will be collected on a subset of the population. Research staff will abstract maternal and neonatal outcomes following delivery and discharge from the hospital. A single maternal follow-up study visit at 6 weeks (4-8 weeks) postpartum will be scheduled to ascertain maternal and neonatal outcomes.