The Risk of Hypertensive Disorders of Pregnancy in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is prevalent during reproductive years. There are limited and conflicting data on whether IBD is associated with elevated risk of hypertensive disorders of pregnancy.

We performed a single-center cohort study using electronic health records of singleton pregnancies delivered 1998-2016. The primary outcome was any hypertensive disorder of pregnancy, including either gestational hypertension or pre-eclampsia. Secondary outcomes included gestational hypertension, pre-eclampsia, preterm delivery, gestational diabetes, severe perineal laceration, and small or large for gestational age birth weight. We used generalized estimating equations, adjusted for age, 1st trimester body mass index and blood pressure, insurance, race, and parity to estimate associations between IBD and outcomes.

We included 364 pregnancies (266 individuals) with IBD and 45,048 pregnancies (32,189 individuals) without IBD. IBD was not associated with hypertensive disorders of pregnancy overall (adjusted odds ratio [aOR] 1.21 95% confidence interval [CI 0.81-1.82], P = 0.35). IBD was associated with an increased odds of pre-eclampsia (aOR 1.65 [95% CI 1.02-2.68]) but not gestational hypertension (aOR 0.82 [95% CI 0.42-1.57]). IBD was associated with preterm delivery (aOR 1.87 [95% CI 1.31-2.68]), small for gestational age (aOR 1.72 [95% CI 1.18-2.51]), and cesarean delivery (aOR 1.72 [95% CI 1.35-2.20]) but not with other secondary outcomes.

Although the risk of hypertensive disorders of pregnancy overall was not increased in pregnancies affected by IBD, there was an increased risk of pre-eclampsia. This may reflect underlying immune-mediated placental dysfunction.