The association between early-life (during pregnancy and after birth) antibiotic exposure and type 1 diabetes: an updated meta-analysis

Background: The impact of antibiotic exposure on type 1 diabetes (T1D) in childhood or adolescence is controversial. This meta-analysis aimed to explore the association between antibiotic exposure in early life (during pregnancy and after birth) and T1D in children or adolescents. Methods: We systematically searched for cohort studies on the association between early-life antibiotic exposure and T1D in children or adolescents, in PubMed, Web of Science, EMBASE, and Science Direct from inception to October 2025. Hazard ratios (HRs) and 95% confidence intervals (95%CIs) were calculated to quantify the association between the early-life antibiotic exposure and the risk of T1D in children or adolescents. Results: Seven studies involving about 7.4 million participants were included in the meta-analysis. Neither the antibiotic exposure during pregnancy (HR = 1.06, 95%CI: 0.98-1.15, p=0.146) nor the antibiotic exposure after birth (HR = 1.03, 95%CI: 0.95-1.11, p=0.491) showed significant differences in the incidence of T1D between the exposed group and the unexposed group. However, a higher incidence of T1D was observed in the exposure after birth compared to unexposed controls among participants born by cesarean section (HR = 1.62, 95%CI: 1.31-2.01, p<0.001). In addition, in subgroup analyzes including sibling comparisons, sex, timing of exposure, frequency of exposure, antibiotic class, and antibacterial spectrum, neither the antibiotic exposure during pregnancy nor the antibiotic exposure after birth found significant differences in the incidence of T1D between both groups. Conclusion: The study did not find the association between early-life (during pregnancy and after birth) antibiotic exposure and T1D. However, antibiotic exposure after birth might increase the risk of T1D among children born by cesarean section.