JAMA Netw Open
Large study supports azithromycin safety during pregnancy
Clinical Takeaway: Prenatal azithromycin exposure doesn't appear to increase the risk of childhood neurodevelopmental disorders. These findings may help reassure clinicians and patients when balancing maternal infection treatment against theoretical fetal neurodevelopmental concerns.
Antibiotic use during pregnancy has raised longstanding concerns about possible effects on fetal neurodevelopment, particularly with macrolide antibiotics such as azithromycin. A new cohort study provides reassuring data regarding neurodevelopmental outcomes after prenatal azithromycin exposure.
Researchers evaluated more than 15,500 mother-infant pairs with a live birth between 2012 and 2023, comparing children exposed to azithromycin in utero with those exposed to other antibiotics or no antibiotics during pregnancy. The primary outcome was a composite of neurodevelopmental disorders, including autism spectrum disorder, attention-deficit/hyperactivity disorder, speech and language disorder, developmental coordination disorder, and behavioral disorder.
Prenatal azithromycin exposure at any point during pregnancy wasn't associated with increased risk of overall neurodevelopmental disorders compared with either no antibiotic exposure or exposure to other antibiotics. The findings remained consistent across multiple developmental outcomes.
In exploratory analyses, azithromycin exposure during late pregnancy was associated with lower risk of overall neurodevelopmental disorders and speech and language disorder compared with exposure to other antibiotics. Late-pregnancy exposure was also associated with lower risk of speech and language disorder compared with no antibiotic exposure. Investigators cautioned that some subgroup findings, particularly for autism spectrum disorder, may have been influenced by small event numbers.
The study included commercially insured women in the northeastern United States, with children followed for a mean of 5.5 years. Approximately 4.8% of mother-infant pairs were exposed to azithromycin during pregnancy.
“In this observational cohort study, late pregnancy azithromycin exposure was associated with a lower risk of neurodevelopmental disorders, especially speech and language disorder,” concluded the study authors. “However, azithromycin prescribing during pregnancy should be approached with caution and interpreted within the context of existing guidelines that recommend β-lactams as the preferred agents.”
Source: Otoo MN, et al. (2026, May 12). JAMA Netw Open. Prenatal Azithromycin Exposure and Risk of Neurodevelopmental Disorders in Children