Fecal Incontinence


Causes of Fecal Incontinence

To control your bowels, the muscles and nerves in your pelvis and in your rectum (the bottom part of your large intestine) have to work properly and in a coordinated way. When everything is working as it should, feces (also called stool) are solid and not liquid by the time they reach the rectum.  In the rectum, circular muscles called sphincters contract like rubber bands to keep feces from leaving the rectum until you are ready to have a bowel movement.  Muscles in the bottom of your pelvis (called pelvic floor muscles) also help keep stool from leaving the rectum until you are ready.

However, if everything doesn’t work as it should, the result can be fecal incontinence. Certain things can increase your risk of incontinence. They include the following conditions.


Diarrhea is defined as an abnormal looseness of the stool, which may also increase how often and how urgently you need to pass stool. As a result, loose feces can be more difficult to hold in your rectum than solid feces. This makes it harder to reach the bathroom on time. 


Constipation is defined as having fewer than three bowel movements a week. When you pass stool less often, your stools tend to get hard and large, and stool can get stuck in your rectum. Once this happens, watery feces often build up behind the hard stool and leak out around it, causing fecal incontinence. Over time, constipation can weaken the sphincter muscles so they’re too weak to control the release of stool.  Frequently straining can also weaken these muscles.  


Hemorrhoids are swollen veins in the lower part of the rectum that may come part way out through the anus (the very end of the rectum). This can keep the sphincter muscles from closing completely. As a result, stool can leak out. 

Muscle and Nerve Damage

Damage to muscles in the pelvis can increase the risk of fecal incontinence. So can damage to the nerves that control these muscles. If the nerves are damaged, you may not even feel the urge to move your bowels. If the nerves or muscles aren’t working as they should, the sphincters may not close tightly, and stool can leak out.

A wide range of health problems can damage these muscles and nerves. They include strokes, diabetes, spinal cord injuries, multiple sclerosis, rectal or anal cancer, Crohn’s disease, and ulcerative colitis. Radiation treatment or surgery can also damage the muscles and nerves. Women who have had a forceps delivery or an episiotomy (a cut the doctor makes in the vaginal area to keep the baby’s head from tearing the vagina during childbirth) may suffer injuries to these muscles and nerves that increase the risk of having fecal incontinence.

Cognitive (Mental) Problems

People with cognitive problems such as dementia may forget to move their bowels or become lost when trying to find the bathroom. In advanced stages, they may lack an understanding of socially proper bowel control or have dietary habits that increase the risk of fecal incontinence.

Risk Factors

Fecal incontinence is not a normal part of aging, but it is more common in older people than younger adults. Many of the problems that contribute to the condition are more common with age. Because damage to nerves and muscles that occurs during childbirth can increase the odds of developing fecal incontinence, women are at higher risk of fecal incontinence than men. 


Untreated fecal incontinence can contribute to:

  • Urinary tract infections
  • Skin rashes and skin ulcers around the anus
  • Lack of sleep – if you are incontinent while sleeping
  • Social withdrawal – if you cut back on the time you spend with other people due to fears that you will not be able to reach a bathroom in time
  • Depression
  • Low self-esteem
  • Falls and fractures – if you leak watery feces on the floor and slip while walking
  • Sexual dysfunction

Last Updated July 2020