Rectal prolapse, intussusception (occult rectal prolapse), solitary rectal ulcer syndrome (SRUS), and rectocele have many features in common and may share a common pathogenesis. Constipation, especially an evacuation disorder, often underlies these abnormalities. Chronic straining may cause intussusception of the rectal mucosa, which in turn can develop into a full-thickness rectal prolapse. A prolapse may cause excessive stitching of the rectal mucosa and cause mucosal injury and ultimately a rectal ulcer. Chronic straining may induce a rectocele.