Disease flare at prior pregnancy and disease activity at conception are important determinants of disease relapse at subsequent pregnancy in women with inflammatory bowel diseases.

Disease flare throughout gestation are not uncommon among women with inflammatory bowel diseases (IBD), and can substantially affect pregnancy outcomes. We aimed to evaluate the effect of prior pregnancy outcome on the risk of disease flare at subsequent pregnancy in women with IBD.Women with IBD attending a multidisciplinary clinic for the preconception, antenatal and postnatal treatment were prospectively recruited during 2011-2018.Overall, 476 IBD women were followed during the study period. Of them, 69 (14.5%) had two pregnancies throughout follow-up period and constituted the study cohort. Among these 69 women, 48 (69.6%) had Crohn's disease and 21 (30.4%) ulcerative colitis. The median interpregnancy interval was 20 [11-32] months. Overall, 34 (49.3%) women experienced disease flare at the subsequent pregnancy. In multivariate analysis, active disease at conception (odds ratio [95% CI]: 25.65 (3.05, 25.52), P < 0.001) and history of disease flare at the previous pregnancy (odds ratio [95% CI]: 4.21 (1.10, 16.58), P < 0.001) were the only independent predictors of disease relapse in current gestation. Rates of hospitalization during pregnancy (14.7% vs. 0, P = 0.02) and preterm delivery (32.4% vs. 5.7%, P = 0.006) were higher, and neonatal birth weight was lower (median 3039 vs. 3300 g, P = 0.03), in those with disease flare as compared to those with maintained remission.History of disease relapse at previous gestation and periconception disease activity were found as important predictors of disease flare among IBD women. These data would facilitate adequate counseling and informed management decisions among reproductive-aged IBD women and their treating physicians.