Anorectal Malformations

Reviewed/Revised Feb 2024
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What are anorectal malformations?

The anus is the hole in your bottom where poop (stool) comes out. The rectum is the end of the large intestine that attaches to the anus.

Anorectal malformations are birth defects of the anus and the rectum.

  • Anorectal malformations are when the opening of the anus is narrow, covered with skin, or missing completely

  • Anorectal malformations block the intestines so your baby can't poop

  • Usually, doctors do surgery to correct an anorectal malformation

Babies with anorectal malformations often have other birth defects.

What are the symptoms of anorectal malformations?

Babies with anorectal malformations don't poop normally after birth. The baby's anus doesn't look normal.

If an anorectal malformation isn't treated, your baby’s intestines may become blocked causing:

  • Pain

  • Irritability

  • Throwing up

  • Swollen belly

How can doctors tell if my baby has an anorectal malformation?

Doctors are able to tell if your baby has an anorectal malformation by examining your baby right after birth. They may also do x-rays.

How do doctors treat anorectal malformations?

To treat an anorectal malformation doctors usually do:

  • Surgery to remove or open the skin that blocks the anus

Sometimes, for severe problems, doctors first do a temporary colostomy. Doctors make a hole in the large intestine and connect it to a hole in the belly. Your baby's poop goes out the hole into a bag until your baby has grown big enough to have another operation to fix the anorectal malformation and close the colostomy.

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