Adjunctive Azithromycin Tied to Fewer Post-Cesarean Infections in Real-World Data
Following a landmark 2016 trial, use of adjunctive azithromycin in unscheduled cesarean deliveries rose from 2.2% to 39.6%, while postpartum infection rates fell from 9.2% to 8%. The difference-in-differences analysis suggests a 20% relative reduction in infections. Researchers estimate this could prevent about 6,000 infections annually.
The analysis drew on over 1.6 million births from a national electronic health record database. The sharp rise in azithromycin use coincided with the 2016 C/SOAP trial, which had demonstrated a near-halving of postpartum infections. The subsequent decline in infection rates among cesarean patients, from 9.2% to 8%, occurred while rates for vaginal births actually rose slightly, strengthening the link to the antibiotic's adoption.
The accompanying editorial argues that these real-world findings support upgrading ACOG's current guidance from merely "considering" azithromycin to formally recommending it for unscheduled, high-risk procedures. The authors also stress that maternal mortality is climbing in the U.S., with infections a leading preventable cause, making consistent implementation of proven prophylaxis a critical opportunity to reduce harm.
This evidence could prompt a shift in clinical guidelines, potentially making adjunctive azithromycin a standard part of care for unscheduled cesarean deliveries. If adopted broadly, it may prevent thousands of infections annually, reducing hospital readmissions, antibiotic courses, and maternal morbidity. However, the analysis is observational, and increased antibiotic use could contribute to antimicrobial resistance. Society may benefit from improved maternal outcomes, but clinicians will need to balance these gains against long-term ecological risks, requiring careful patient selection and ongoing surveillance.