Purpose: Former studies have suggested that women with Crohn’s disease (CD) and ulcerative colitis (UC) have a decreased chance of a live born child after assisted reproductive technology (ART) treatment. It is debated whether corticosteroids before ART may improve outcomes, either by decreasing inflammatory bowel disease-related inflammation or increasing endometrial receptivity. We examined the efficacy of corticosteroids before embryo transfer in women with CD and UC. Patients and Methods: Our cohort study is based on nationwide Danish health registries, comprising women with CD and UC receiving an embryo transfer (1 January 2006 through 2017). Exposed cohorts constituted women with CD and UC who had received corticoster-oids within three months before embryo transfer, and the unexposed cohorts women with CD and UC who did not receive corticosteroids. Our primary outcome was live birth. We controlled for multiple covariates in the analyses. Results: We examined 2408 embryo transfers. In patients with CD, 114 embryo transfers were preceded by a corticosteroid prescription, and 964 were not. The corresponding numbers in UC were 122 and 1208, respectively. The adjusted odds ratio (aOR) for live birth in women with CD receiving corticosteroids before embryo transfer, relative to women with CD not receiving corticosteroids, was 0.89 (95% CI 0.49–1.63). The corresponding aOR in UC was 0.98 (95% CI 0.55–1.74). Conclusion: Corticosteroids prior to ART in women with CD and UC did not increase the chance of a live born child. The exact impact of corticosteroids prior to embryo transfer in patients with CD and UC still remains to be determined.