Meconium ileus can happen when a baby with cystic fibrosis can’t pass their first poop, called meconium. It’s a serious condition that requires prompt diagnosis and treatment. Treatment involves enemas and possibly surgery.

image of a newborn baby's feetShare on Pinterest
Getty Images/Vera Livchak

Meconium ileus is a serious issue that affects up to 20% of newborns with cystic fibrosis. Learning about this condition can help you know what to look out for and when to get help.

This article will give you a brief yet clear understanding of the causes, symptoms, diagnosis, treatment options, and what problems can happen.

A newborn’s first bowel movement is composed of a sticky substance called meconium. If the small intestine slows or doesn’t move the stool through it, it’s called an ileus. So, if a newborn can’t pass their first stool – their meconium stool – it’s called a meconium ileus and can lead to a potentially dangerous blockage of the small intestine.

Meconium ileus can happen for many reasons. One of the most common reasons is that the baby has cystic fibrosis (CF).

Meconium ileus can happen in babies without CF, but 80%–90% of babies with this condition have CF. Meconium ileus is often one of the first indications that your baby may have CF. About 20% of babies with CF in the United States will have this complication at birth.

CF makes the mucus in the body thicker than usual. Because of this, meconium can’t move through the body in a typical way, leading to meconium ileus. The intestines above the blockage then become enlarged. As your baby starts to eat, food can’t get through, and your baby will vomit.

Meconium ileus can be either simple or complex. Simple ileus means meconium blocks your baby’s small intestines, but there are no other complications. With complex meconium ileus, your baby’s meconium builds up so much that it causes extreme pressure and swelling in the intestines. This situation can lead to serious complications.

There are multiple symptoms of meconium ileus in babies with CF. Several symptoms may be present within hours of your baby’s birth. These include:

  • meconium that doesn’t pass within the first 48 hours of life
  • green vomit
  • swollen abdomen
  • redness of abdomen
  • breathing problems from the swollen abdomen
  • abdominal tenderness
  • fever

Doctors diagnose meconium ileus using several techniques:

Your doctor will work with you to make a delivery plan if an ultrasound during pregnancy shows your baby has meconium ileus. This plan will include where you deliver and post-delivery care of your baby. Sometimes, this means giving birth at a different hospital than you originally planned so your baby can receive the best care.

If your baby has a meconium ileus, your doctor will also order tests after birth to find out whether your baby has CF. These tests include a sweat test and the routine newborn screen blood test.

Your healthcare team will stabilize your baby if they suspect meconium ileus. The first steps are:


Simple meconium ileus is treated with enemas to clean out the meconium blockage. The enema may have medication to help break down and soften the thick stool.

Your baby will have a medical imaging procedure called fluoroscopy for enemas. This procedure passes X-rays through the body. It creates a video image of your baby’s tissues.


Surgery may be necessary if the enema doesn’t remove the blockage or if there’s complex ileus.

Surgery removes the meconium and sometimes part of the intestine damaged by the blockage. The surgeon saves as much healthy intestine as possible. They’ll sew the two ends back together if the intestine is healthy enough.

An ileostomy is often needed instead of sewing the pieces together. In this procedure, the surgeon brings the intestine’s open ends through the abdominal wall. The ends of the intestine form a stoma on your baby’s belly. It looks like a small pinkish, round piece of tissue. Your baby will wear a pouch to collect waste from the intestines.

After surgery, your baby may have more enemas until the meconium is all removed. The doctor may also order fluids through a tube into your baby’s nose and stomach. The intestine ends are later put back together with another surgery. This surgery takes place weeks or months later.

Your baby may need emergency surgery if their intestines twist or the blockage has caused a hole in the intestines.

Several serious complications can develop from meconium ileus, including:

The main risk factor for meconium ileus is having cystic fibrosis. CF is a genetic condition that causes your baby to have unusually thick and sticky secretions. This disease affects the lungs, pancreas, digestive tract, and other organs.

The outlook for babies with meconium ileus has improved with better treatment and operations. There’s also better management of infections and caring for the special nutritional needs of babies with CF.

One small study indicated that babies with CF who develop a meconium ileus may also have worse lung function, growth, and nutrition over time than babies that don’t have this complication. Meconium ileus may be an early predictor of the overall outlook of a child with CF.

Another small study indicated that breastfeeding may protect your baby in the first 12 months from negative outcomes from meconium ileus in babies with CF.

With early diagnosis and treatment, the outlook is good for your baby’s nutrition intake, lung function, and risk of infection. The outlook is poor if your baby has a meconium ileus that is left untreated.

Can I do anything to prevent my baby from getting meconium ileus?

You can’t prevent meconium ileus. CF is an inherited disease. If you’re thinking of becoming pregnant, you can get CF carrier screening to know whether you’re at risk of having a baby with CF.

Is meconium plug syndrome the same thing as meconium ileus?

No, meconium plug syndrome is a different condition. It usually affects preterm babies that have low birth weight. In this condition, the meconium blockage occurs in the large intestines, not the small intestine.

What percentage of babies with cystic fibrosis survive meconium ileus?

Survival rates have greatly improved with a better understanding of CF. Today, survival rates for both simple and complex meconium ileus are over 80%.

Meconium ileus is a challenge that primarily affects newborn babies with cystic fibrosis. You’ll see symptoms within the first few days or even hours of life.

Prompt diagnosis and treatment provide your baby with the best possible outcome.