Causes of loss of bowel control include constipation, nerve damage and muscle damage, according to Mayo Clinic. Loss of storage capacity in the rectum may cause bowel incontinence as well.
Damage to nerves that control sphincter movement or sense stool may occur due to spinal cord injury, delivery, persistent straining when passing bowels, diabetes and stroke, explains Mayo Clinic. Multiple sclerosis and chronic constipation may also injure the nerves. Episiotomy and forceps delivery may damage sphincter muscles around the anus, leading to loss of bowel control.
Loss of storage capacity in the rectum may result from radiotherapy, bowel inflammation or surgery, according to Mayo Clinic. Surgery scars or stiffens rectal walls and can damage nerves or muscles that control the anal sphincter. Chronic constipation may cause fecal impaction, which stretches and weakens rectal muscles, leading to uncontrolled passing of watery stools. Diarrhea, which is the regular passing of liquid stools, may exacerbate the problem.
Risk factors for bowel incontinence include dementia, physical disabilities and certain injuries, explains Mayo Clinic. The condition is common in middle-aged and older women. If left untreated, the condition may lead to anal itching, irritation and ulcers. People who suffer from fecal incontinence may experience frustration, depression and embarrassment as well.