The Association Between Caesarean Section and Inflammatory Bowel Disease in Childhood and Young Adulthood: Findings From 2 Retrospective Cohort Studies

Objective: The aim of the study was to examine the association of Caesarean section (CS) with inflammatory bowel disease (IBD) in Nova Scotian children. Methods: The study consisted of 2 retrospective cohorts in the Canadian province of Nova Scotia: all births between 1988 and 2014 (n = 262,729) linked with a clinical registry of all children diagnosed with IBD at the IWK Health Centre, Halifax (Clinical Cohort) and all births from 1989 to 1993 (n = 42,999) linked with provincial administrative health data (Administrative Cohort). The primary outcome was a diagnosis of IBD; the outcome in the Administrative Cohort was ascertained using a previously validated algorithm. Information on the exposures and confounding variables was obtained from the Nova Scotia Atlee Perinatal Database. The association between CS and time to diagnosis of IBD was examined using survival analysis. Results: The population incidence of IBD in the Clinical and Administrative Cohort were 13.0 and 20.6, respectively, per 100,000 person-years; 23% and 19% of children were born by CS in the 2 cohorts. There was no association of CS with IBD in the 2 cohorts. Conclusions: Findings from 2 population-based cohorts in Atlantic Canada did not provide any evidence for an association between CS and IBD in childhood and young adulthood.