When a baby is born with a problem with their anus or rectum that interferes with the normal passing of stool during bowel movements, this is called an anorectal malformation. Anorectal malformation is a congenital condition, meaning that it is present at birth. The anus is the opening at the end of the gastrointestinal tract where stool leaves the body during a bowel movement. The rectum is the part of the large intestine just above the anus.

An anorectal malformation happens when the anus or rectum does not develop properly, is in the wrong place, or is missing or blocked. Anorectal malformations can cause problems with having bowel movements. Children with anorectal malformations can have other congenital conditions that affect different parts of their body.

The exact cause of the condition is not known, but the treatment for anorectal malformation is surgery to help the child pass stool. Specialists at the Washington University Pediatric Colorectal Center will work with you to find the best solution for this complicated problem.

Types of Anorectal Malformations

There are different kinds of anorectal malformations. They can be different for males and females. Types of anorectal malformations include:

Imperforate anus: When there is no anal opening

Fistula: When the rectum has an abnormal opening to another part of the body, such as:

  • Recto-perineal fistula: The rectum ends at the space between the anus and sex organs, called the perineum
  • Recto-urethral fistula: The rectum ends at the tube that carries urine from the body, called the urethra
  • Recto-bladderneck fistula: The rectum ends at the urethra just below the organ that stores urine, called the bladder
  • Recto-vestibular fistula: The rectum ends at the female sex organ called the vagina

Rectal atresia: When the rectum does not connect to the anus

Cloaca: When the urethra, vagina and rectum are all joined together instead of being three separate channels


Anorectal malformations can cause problems with bowel movements. Symptoms of an anorectal malformation may include:

  • Inability to pass stool
  • Intestinal obstruction
  • Vomiting
  • Bloating or swollen belly
  • Serious infections and sepsis
Testing and Diagnosis

When a child is born, the doctor does a thorough physical exam of the baby from head to toe. The doctor will usually diagnose an anorectal malformation during this exam if the anus is not open or in the right place.

Another sign of anorectal malformation can be if a child does not have a bowel movement in the first 48 hours after birth.

The doctor may order imagining tests to check for anorectal malformation. They might also order other tests to check for conditions that are common in children with anorectal malformations.

Imaging tests for anorectal malformations include:

  • Abdominal x-rays to see where the malformation is located and to check for problems with the spine
  • Abdominal and spinal ultrasounds to look at the urinary tract and spine
  • Echocardiogram to check for heart defects
  • Other types of imaging and testing, depending on the child’s condition

Our imaging specialists at St. Louis Children’s Hospital are nationally recognized experts ranked by U.S. News & World Report. We use the most advanced imaging techniques to understand your child’s exact situation and inform our treatment plan.


Treatment depends on the type of anorectal malformation, as well as the child’s overall health. Surgery to correct the anorectal malformation is usually necessary. This can sometimes require multiple surgeries.

Most anorectal malformations are diagnosed and treated with surgery shortly after birth.

In some cases, there might be a surgery called a colostomy. This procedure connects the colon to an opening in the abdominal wall, called a stoma, so that the child can pass stool. Then, when the child is older, the surgeon may be able to correct the anorectal malformation and close the stoma so the child can pass stool through the bottom.

If your child needs a colostomy, our specialists will help you learn to take care of the colostomy. The team at the Washington University Pediatric Colorectal Center helps families transition from hospital to home, and is available for all of your child’s follow-up care needs. Our program also offers a family support group to connect families and provide resources.

What to Expect

Patients with anorectal malformations often need further management outside of the neonatal, or newborn, period. The Washington University Pediatric Colorectal Center has extensive expertise in management of these cases.

You will meet with a pediatric gastroenterologist and pediatric surgeon to discuss your child’s condition and treatment options. We will review any previous imaging and tests, and may use additional tests to prepare for the surgery. We provide personalized care based on your child’s needs and your family’s goals.

Why WashU?

At the Washington University Pediatric Colorectal Center, we provide high-quality care to children with complex colorectal issues, including anorectal malformations.

Goal-setting is an important part of our practice. We personalize your child’s care based on your family’s goals and what is best for your child’s health.

You have access to nationally-recognized experts in pediatric colorectal care—including gastroenterology, radiology, and surgery—at the Pediatric Colorectal Center. Our team works together with you to achieve your goals and find the best solution for your child.

Book an Appointment

To talk to a member of the Pediatric Colorectal Team,
please call 314-454-6022 or request an appointment online.