Rectal prolapse is most common in children and older adults, especially women. It occurs when part or the entire rectal wall slides out of place. Rectal prolapse usually causes fecal incontinence.
The three types are:
- Partial prolapse, or mucosal prolapse. The lining (mucous membrane) of the rectum slides out of place and usually sticks out of the anus. This can happen when straining to have a bowel movement. It is most common in children younger than 2 years.
- Complete prolapse. The entire wall of the rectum slides out of place and usually sticks out of the anus. At first, this may occur only during bowel movements. Eventually, it may occur when standing or walking. In some cases, the prolapsed tissue may remain outside the body all the time.
- Internal prolapse (intussusception). Part of the wall of the large intestine (colon) or rectum may slide into or over another part, like the folding parts of a toy telescope. The rectum does not stick out of the anus. It is most common in children and rarely affects adults. In children, the cause is usually not known. In adults, it is usually related to another intestinal problem, such as a growth of tissue in the wall of the intestines, such as a polyp or tumor.