PREGNANT individuals with inflammatory bowel disease (IBD) may face significantly increased risks of adverse pregnancy and neonatal outcomes, even when standard clinical and biochemical assessments suggest the disease is under control, according to new international research.
Published as part of a prospective cohort study spanning 2017 to 2023, the findings reveal that intestinal ultrasound (IUS) provides a more accurate prediction of complications such as prematurity, low birth weight, preeclampsia, and gestational diabetes than clinical scores or faecal calprotectin (FCP) tests alone.
Researchers examined 377 pregnant individuals with IBD, more than half of whom had Crohn’s disease, recruited from three specialised IBD pregnancy clinics. Clinical assessments, FCP levels, and IUS were used throughout pregnancy, with ultrasound offered in the first or second trimester based on referral timing.
The study found that a bowel wall thickness over 6mm on IUS in the second trimester was linked to a four-fold higher risk of premature birth and double the risk of low birth weight delivery. Increased intestinal blood flow (hyperemia) on IUS in the second trimester was associated with a three-fold increased risk of preeclampsia. Even a 1mm increase in bowel wall thickness correlated with higher risk of gestational diabetes.
Importantly, the study found poor agreement between traditional clinical assessments or FCP and disease activity shown on ultrasound, particularly in those with Crohn’s disease. This suggests that many patients with active intestinal inflammation may go undetected using standard methods alone.
“Our data show that ultrasound-detected inflammation, even in the absence of symptoms, matters for pregnancy outcomes,” said lead author Dr Ralley Prentice from Monash University. “We need to re-evaluate how we monitor pregnant patients with IBD.”
The researchers call for routine use of IUS in antenatal care for patients with IBD, emphasising its potential to guide treatment decisions and improve outcomes for both mother and baby.
Reference
Prentice RE 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. Gastroenterol. 2025;DOI: 10.1053/j.gastro.2025.03.016.
