Imperforate anus, also called anorectal malformation, is a congenital (existing before birth) defect that happens early in pregnancy, while a baby is still developing.
With this defect, the baby’s anal opening (where stool exits), the rectum (the last part of the large intestine), and nerves that tell the body when it’s “time to go” do not develop properly, preventing the child from being able to have normal bowel movements.
In a baby with imperforate anus/anorectal malformation, any of the following can happen:
At birth, doctors will always check to make sure that a newborn baby’s anus is open and in the correct position. Newborns pass their first stool within 48 hours of birth, so internal malformations will usually be detected quickly. If an issue is found, the doctor will do a number of tests to better understand the problems and to develop a long-term plan for the best outcome. These tests might include:
These malformations will always require specialized types of surgical repair, but the exact procedure will depend on the type and severity of the defect, if there are any associated health conditions (see below), and the child's overall health. Even though corrective surgery may restore some function, important nerves and muscles that tell your child when the rectum is full of stool and help keep the contents inside may be missing or damaged, so starting a bowel management program when they reach toilet-training age may help them become clean.
Toilet training can be started at the usual age, around three years old. Children who have had imperforate anus generally gain bowel control more slowly. Depending on the type of malformation and the operations done to repair it, some children have difficulty maintaining good bowel control, and may need to participate in a bowel management program. Each child’s situation will be slightly different and will be determined with the help of your child’s healthcare team.
Children who had a malformation called a rectoperineal fistula as well as those with rectobulbar fistula and rectovestibular fistula are usually able to gain good control over their bowel movements after surgical repair, provided they can avoid constipation.
However, those with more difficult types of anorectal malformation, such as rectoprostatic fistula, rectobladderneck fistula, and cloaca may need to participate in a bowel management program to help them achieve control over their bowel movements and remain clean.
The condition affects one in 5,000 babies, and it is slightly more common in males than in females. No one knows why some babies are born this way, but in some cases, there is a family history.
Almost 50 percent of patients with imperforate anus/anorectal malformations have other defects, including:
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