Anal Fissures

Anal fissures are very common in young infants, but may occur at any age. The rate of anal fissures drops with age. Fissures are much less common among school-aged children than infants.

In adults, fissures may be caused by passing large, hard stools, or by having diarrhea for a long time. Other factors may include: 

• Decreased blood flow to the area in older adults

• Too much tension in the sphincter muscles that control the anus

Anal fissures are also common in women after childbirth and in persons with Crohn's disease.