Outcomes of infants born to mothers with inflammatory bowel disease: a population-based cohort study

Limited population-based data on inflammatory bowel disease (IBD) and pregnancy outcomes exist. The purpose of this study is to determine the association between maternal IBD status and adverse pregnancy outcomes.

Using computerized birth records of infants born to mothers with Crohn's disease (CD) or ulcerative colitis (UC) and mothers without diagnoses of IBD (no-IBD) in Washington State, we performed a cross-sectional retrospective study to determine gestational age, birth weight, and congenital malformations.

Preterm delivery was seen in 15.2% of CD births, 10.4% of UC births, and 7.2% of no-IBD births. Low birth weight was found in 16.8% of CD births, 7.6% of UC births, and 5.3% of no-IBD births. Smallness for gestational age was present in 15.2% of CD births, 10.5% of UC births, and 6.9% of no-IBD births. Only CD births were at significantly increased risk of preterm delivery (p < 0.0025), low birth weight (p < 0.001), and smallness for gestational age (p < 0.001). Congenital malformations were more commonly recorded in UC births than in controls (7.9% vs 1.7%, p < 0.001), whereas 3.4% of CD births had malformations recorded. Using multivariable logistic regression, CD births were more likely to be preterm (odds ratio [OR] = 2.3, 95% CI = 1.4-3.8) and have low birth weights (OR = 3.6, CI = 2.2-5.9) and smallness for gestational age (OR = 2.3, CI = 1.3-3.9). UC births were more likely to have congenital malformations reported (OR = 3.8, CI = 1.5-9.8).

Maternal IBD is associated with increased odds of preterm delivery, low birth weight, smallness for gestational age (CD), and reporting of congenital malformations (UC).