%0 Journal Article %A Simone N Vigod %A Paul Kurdyak %A Hilary K Brown %A Geoffrey C Nguyen %A Laura E Targownik %A Cynthia H Seow %A M Ellen Kuenzig %A Eric I Benchimol %T Inflammatory bowel disease and new-onset psychiatric disorders in pregnancy and post partum: a population-based cohort study %D 2019 %R 10.1136/gutjnl-2018-317610 %J Gut %P 1597-1605 %V 68 %N 9 %X Objective Patients with inflammatory bowel disease (IBD) have an elevated risk of mental illness. We determined the incidence and correlates of new-onset mental illness associated with IBD during pregnancy and post partum.Design This cohort study using population-based health administrative data included all women with a singleton live birth in Ontario, Canada (2002–2014). The incidence of new-onset mental illness from conception to 1-year post partum was compared between 3721 women with and 798 908 without IBD, generating adjusted HRs (aHR). Logistic regression was used to identify correlates of new-onset mental illness in the IBD group.Results About 22.7% of women with IBD had new-onset mental illness versus 20.4% without, corresponding to incidence rates of 150.2 and 132.8 per 1000 patient-years (aHR 1.12, 95% CI 1.05 to 1.20), or one extra case of new-onset mental illness per 43 pregnant women with IBD. The risk was elevated in the post partum (aHR 1.20, 95% CI 1.09 to 1.31), but not during pregnancy, and for Crohn’s disease (aHR 1.12, 95% CI 1.02 to 1.23), but not ulcerative colitis. The risk was specifically elevated for a new-onset mood or anxiety disorder (aHR 1.14, 95% CI 1.04 to 1.26) and alcohol or substance use disorders (aHR 2.73, 95% CI 1.42 to 5.26). Predictors of a mental illness diagnosis were maternal age, delivery year, medical comorbidity, number of prenatal visits, family physician obstetrical care and infant mortality.Conclusion Women with IBD were at an increased risk of new-onset psychiatric diagnosis in the postpartum period, but not during pregnancy. Providers should look to increase opportunities for prevention, early identification and treatment accordingly. %U https://gut.bmj.com/content/gutjnl/68/9/1597.full.pdf