Antibiotics in Pregnancy and Infancy Not Linked to Autoimmune Risk

A nationwide Korean cohort study published in PLOS Medicine followed more than 5 million children to test whether antibiotics given during pregnancy or in the first six months of life raise the risk of autoimmune disease. The autoimmune diseases of interest were type 1 diabetes, juvenile idiopathic arthritis, Crohn’s disease, ulcerative colitis, systemic lupus erythematosus, and Hashimoto’s thyroiditis.

The researchers found no overall association between antibiotic exposure during pregnancy or early infancy and the development of autoimmune disease.

To reduce bias from infections and family factors, they applied inverse probability weighting and sibling-matched analyses, both of which “showed null association between antibiotic exposure and autoimmune diseases in children.”

Some Subgroups Showed Modest Autoimmune Risk Increases

• Crohn’s disease: “maternal use of cephalosporins or antibiotics during first or second trimester was associated with a small increased risk of Crohn’s disease in pregnancy analysis” – Choi et al., 2025
• Autoimmune thyroiditis: “antibiotic exposure in males or during the first two months of life was associated with a modestly increased risk of autoimmune thyroiditis in infancy analysis.” – Choi et al., 2025

Overall, the findings are reassuring for families and clinicians: when antibiotics are prescribed for real infections in pregnancy or infancy, they do not appear to raise children’s long-term risk of autoimmune disease.

Citation

Choi, E.-Y., et al. (2025) Exposure to antibiotics during pregnancy or early infancy and the risk of autoimmune disease in children: A nationwide cohort study in Korea. PLoS Medicine, 22(8). DOI: 10.1371/journal.pmed.1004677. https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1004677