Abstract
BACKGROUND: With increasing use of intrapartum antibiotic prophylaxis (IAP) for the prevention of early-onset Group B streptococcus (GBS) infections, there is concern about its long-term consequences on child health. OBJECTIVES: To synthesise the evidence of IAP exposure on autoimmune-related diseases, obesity in childhood and microbial diversity in infants. SEARCH STRATEGY: PubMed, Web of Science, Emcare, Embase and Scopus were searched from inception until 17 July 2025 for related observational studies. SELECTION CRITERIA: The exposure group comprised mothers with full-term vaginal deliveries who underwent GBS screening and received IAP, while the comparator group included mothers with full-term vaginal deliveries with GBS-negative results and no IAP exposure. DATA COLLECTION AND ANALYSIS: Results were pooled using fixed or random-effects meta-analysis based on heterogeneity assessed by the I(2) statistic. MAIN RESULTS: Sixteen studies were eligible to be included in the meta-analysis. IAP exposure was associated with an increased risk of autoimmune-related disease (6 studies, relative risks (RRs) = 1.73; 95% confidence interval [CI]: 1.08-2.78; I(2) = 94.8%). Subgroup analysis based on types of autoimmune-related diseases showed a significant increase in the risk of atopic dermatitis (3.44; 1.60-7.37). There was a modest increase in child BMI (2 studies, standardised mean difference = 0.05; 95% CI: 0.03-0.06; I(2) = 50.09%), but not BMI z-score (3 studies, 0.13; 0.03-0.29; I(2) = 72.05%) or microbiome diversity in infants (6 studies, -0.09; -0.20 to 0.02; I(2) = 0.00%) born to pregnant women exposed to IAP compared to non-exposed women. CONCLUSION: IAP exposure is associated with an increased risk of autoimmune-related disease and a modest increase in child BMI. TRAIL REGISTRATION: PROSPERO (CRD42023493413).