Factors Associated with Inflammatory Bowel Disease Flare During Pregnancy Among Women with Preconception Remission.

Background: The factors associated with inflammatory bowel diseases (IBD) relapse throughout gestation in those with preconception remission remain unknown.

Aims: We aimed to investigate disease and pregnancy course among IBD women with quiescent disease at conception.

Methods: Women with IBD attending a multidisciplinary clinic for preconception, antenatal and postnatal treatment were prospectively recruited during 2011-2018.

Results: Overall, 298 women with IBD with quiescent disease at the time of conception constituted the study cohort. Of these, 112 (37.6%) women experienced disease flare during pregnancy. The risk of disease relapse was higher in those with ulcerative colitis (UC) as compared to those with Crohn's disease (CD) (48.1% vs. 31.8%, P = 0.005). The proportion of women with prior IBD-related gastrointestinal surgery was lower in those who experienced disease flare up (13.4% vs. 26.3%, P = 0.009). The use of biologic therapy at the time of conception was associated with lower rates of disease relapse (25.0% vs. 43.9%, P = 0.001). In multivariate analysis, use of conventional medications or no treatment (aOR [95% CI]: 2.0 (1.12, 3.57), P = 0.02) and lack of prior history of IBD-related surgery (aOR [95% CI]: 3.13 (1.37, 7.14), P = 0.007) were independently positively associated with disease relapse. Rates of hospitalization during pregnancy (21.4% vs. 2.2%, P < 0.001) and preterm delivery (22.3% vs. 9.1%, P = 0.002) were higher, and birthweight was lower (median 2987 vs. 3153 grams, P = 0.05) in those with disease flare as compared to those who maintained remission.

Conclusion: Prior IBD-related surgery and biologic therapy were found as independent protective factors against relapse during pregnancy among women with quiescent disease at conception.