Intestinal Ultrasound Activity in Pregnancy Predicts Adverse Outcomes in Women With Inflammatory Bowel Disease
Results of an international prospective cohort study demonstrate that active disease on intestinal ultrasound (IUS) is a strong and independent predictor of adverse pregnancy and neonatal outcomes among pregnant women with inflammatory bowel disease (IBD), outperforming traditional clinical and biochemical measures.
From 2017 to 2023, 377 pregnant participants with IBD, including 198 with Crohn disease, were enrolled across 3 specialized IBD pregnancy centers. Clinical assessments and fecal calprotectin (FCP) testing were performed each trimester and postpartum, while IUS was conducted in the first or second trimester when feasible. The primary outcomes included prematurity, low birth weight, preeclampsia, and gestational diabetes. Regression analyses estimated associations between IUS activity and outcomes, and Cohen κ coefficients measured concordance among IUS, FCP, and clinical scores.
Among the 234 women who underwent IUS, a maximal bowel wall thickness (BWT) >6 mm in the second trimester was strongly predictive of adverse outcomes. Specifically, BWT >6 mm conferred a 4-fold increased risk of prematurity (RR, 4.01; 95% CI, 1.26-12.72) and a 2-fold increased risk of low birth weight (RR, 2.19; 95% CI, 1.01-4.72). Hyperemia detected on IUS was associated with a 3-fold increased risk of preeclampsia (RR, 3.46; 95% CI, 1.03-11.12). Moreover, each 1-mm increase in BWT correlated with higher gestational diabetes risk (RR, 1.08; 95% CI, 1.088-1.089). Agreement between IUS findings and either FCP or clinical indices was poor, particularly for Crohn disease.
These findings suggest that IUS should be integrated into antenatal monitoring to refine risk stratification and inform therapeutic decisions for pregnant individuals with IBD.
Reference:
Prentice RE, Flanagan EK, Wright EK, et al. Active inflammatory bowel disease on intestinal ultrasound during pregnancy is associated with an increased risk of adverse pregnancy and neonatal outcomes independent of clinical and biochemical disease activity. Gastroenterology. 2025;169(4):647-662.
