Can colonoscopy diagnose bowel endometriosis?

Often, no—colonoscopy does not reliably diagnose bowel endometriosis because many lesions grow on the outside of the bowel or within deeper layers, while the inner lining can look completely normal. Even when symptoms are significant, biopsies taken from the bowel lining may miss disease that isn’t on the surface.

Colonoscopy can still be helpful when symptoms like rectal bleeding are present, because it can evaluate for other conditions inside the bowel. For mapping suspected bowel endometriosis, we more commonly rely on specialized pelvic imaging such as transvaginal or transrectal ultrasound with bowel preparation and pelvic MRI to understand location, depth, and surgical complexity. If you’re wondering whether bowel endometriosis could be contributing to your symptoms, our team can review your history and imaging and walk you through the next best steps.