Anal stricture (also called "anal stenosis") is a medical problem that is not common; it may be "congenital" (a baby is born with a medical problem), but usually if it does happen it is after "anorectal surgery", which is surgery in the area of the rectum and anus. This may cause "stricture" (when a passage in the body becomes too narrow) of the anal canal, which leads to hard or painful bowel movements. When anal stenosis does occur it is usually after a "hemorrhoidectomy," which is the surgical removal of hemorrhoids; this is the cause in 90% of cases of anal stenosis.