S1635 Ultrasound-Based Detection of IBD Activity in Pregnancy: A Predictor of Adverse Outcomes?

Introduction: Monitoring inflammatory bowel disease (IBD) during pregnancy is challenging due to limitations in conventional diagnostic modalities and a lower reliability of laboratory markers. Intestinal ultrasound (IUS) provides a non-invasive, radiation-free method for evaluating disease activity in this population. Prior studies suggest that active IBD is associated with increased risks of adverse obstetric and clinical outcomes. This study investigates whether IUS-detected disease activity during pregnancy predicts these outcomes. Methods: Unique pregnancies in patients with IBD who underwent IUS during pregnancy and delivered were identified through the electronic medical record. Pregnancies were stratified by activity in IUS findings and univariate analyses were used to compare clinical characteristics and outcomes between groups. Baseline features, including demographics, pregnancy characteristics, IBD characteristics, fecal biomarkers (calprotectin/lactoferrin), and visualization of known disease location were noted. Outcomes, including changes in IBD management post-IUS, postpartum flares, disease activity at next follow-up, and adverse pregnancy outcomes were also recorded. Results: A total of 32 unique pregnancies were identified of which 7 had active disease by IUS. The median age at IUS was 31 years (IQR: 28–34), with a median gestational age of 23 weeks (IQR: 19–31). The majority were non-Hispanic Whites (75%). No significant associations were found between IUS activity and trimester, BMI, IBD subtype, or therapy class. However, active disease by IUS significantly correlated with clinical activity (partial Mayo or Harvey-Bradshaw Index) at IUS (P = 0.004) and fecal biomarkers within ±90 days of IUS (P = 0.014). Four patients with activity on IUS had a management change post-scan; the remaining 3 had already undergone empiric escalation prior to IUS. Active disease by IUS was significantly associated with post-partum flares (P = 0.006) and active disease at follow-up (P = 0.045). Pre-eclampsia and pre-term birth were the most frequent obstetric complications (9%), though no significant difference in complications was observed by activity in IUS. Conclusion: IUS-detected disease activity during pregnancy significantly correlates with clinical symptoms, fecal biomarkers, persistent disease activity, and postpartum flares. These findings support the role of IUS as a valuable tool for disease monitoring and risk stratification in pregnant patients with IBD.