Monitoring inflammatory bowel disease during pregnancy: Current literature and future challenges

Table 1 Overview of various disease monitoring modalities and their pros/cons in pregnant inflammatory bowel disease patients

Monitoring modality	Pros	Cons
Lower endoscopy
Colonoscopy	Gold standard of disease monitoring	Limited studies
	Early studies show no difference in adverse events between pregnant IBD patients who underwent colonoscopy and who did not undergo colonoscopy	Provider/patient hesitancy due to procedural and anesthetic concerns
Flexible sigmoidoscopy	Can be performed without sedation No case reports of any procedure-related complications	Limited studies
Radiologic studies
Ultrasound	Safest form of radiologic imaging	Sensitivity in pregnancy unknown
	Contrast-enhanced ultrasound shown to have good results in IBD
Magnetic resonance imaging	No use of damaging ionizing radiation	Currently no well-controlled studies of the teratogenic effects of gadolinium contrast in pregnant women have been performed and the fetal risk is unknown
	Can detect luminal and extraluminal abnormalities
	Long-term safety after exposure to MRI trimester of pregnancy showed no increased risk of harm to the fetus or in early childhood
Biomarkers
Albumin	Low albumin shown to be predictor of poor outcomes in IBD	Limited utility in pregnancy due to pregnancy-induced hemodilution resulting in lower albumin values
ESR	Generally a good marker of inflammation and reflects disease activity	Limited utility in pregnancy due to physiologic increase in ESR (2-3 x upper limit of normal)
CRP	Levels are only slightly raised in normal pregnancy and are still under the normal limits	May not accurately reflect disease activity in second and third trimester
	CRP higher in clinically active pregnant IBD patients at preconception and first trimester compared to clinically inactive pregnant IBD patients	Limited studies in pregnant IBD population
FCP	Measure of GI mucosal inflammatory activity detected prior to signs of systemic inflammation	Conflicting evidence for utility of FCP in IBD during pregnancy
	Multiple studies showing correlation between FCP levels and non-invasive disease activity scores in CD and UC	Limited studies with actual endoscopic data to evaluate clinical activity

IBD: Inflammatory bowel disease; CD: Crohn's disease; MRI: Magnetic resonance imaging; UC: Ulcerative colitis; CRP: C-reactive protein; ESR: Erythrocyte sedimentation rate; FCP: Fecal calprotectin.