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Pyloric Stenosis

What is pyloric stenosis?

Pyloric stenosis (pronounced pie-LOR-ik sten-OH-sis) is a thickening of the muscle at the end of the stomach that can block or slow down the passage of food from the stomach to the intestine. This can cause a baby to vomit, often in a forceful way (called projectile vomiting).

Who gets pyloric stenosis?

This is a common problem in babies between 2 weeks and 3 months old. It affects about 1 in every 300 babies.

What are the symptoms?

All babies spit up or vomit sometimes. Those with pyloric stenosis spit up after most feedings. Over time, the problem worsens so that your baby spits up or vomits more often and more forcefully. Eventually, your baby may not be able to keep down any milk or formula.

Vomiting may hurt your baby’s stomach. But usually babies with pyloric stenosis don’t seem uncomfortable or sick, except that they vomit. They may appear hungry again soon after vomiting because they aren’t keeping down and processing their food.

If your baby vomits often for a few days, they may produce less stool (feces) and may start to lose weight. Your baby may not have enough fluid in their body, a condition called dehydration. This can be deadly. A dehydrated baby may be sluggish and less active. The top of the head and the eyes may be sunken. Your baby may not urinate as often as usual.

How do you diagnose pyloric stenosis?

Babies with this condition usually have a history of vomiting often and with increasing force. So your baby’s history will be an important clue. The doctor will examine your baby’s stomach to feel for the thickened muscle. Often it feels like an olive. Usually pyloric stenosis is best diagnosed by an ultrasound. Some babies may need an X-ray to check the muscle or to tell whether they may be vomiting for some other reason. For this type of X-ray, your baby will need to swallow a chalky liquid called barium so the digestive tract shows up in the image.

What is your experience with pyloric stenosis at Children’s?

We treat many babies with pyloric stenosis at Children’s and take care of 40 to 60 children with this condition every year. Our surgeons are experienced at performing the operation that your child with pyloric stenosis needs to eat well and thrive.

When you come to Children’s, you have a team of people to care for your child before, during and after surgery. Along with your child’s surgeon, you are connected with nurses, dietitians, child life specialists, social workers and others. We work together to meet all of your child’s health needs and help your family through this experience.

Since 1907, Children’s has been treating children only. Our team members are trained in their fields and also in meeting the unique needs of children. For example, the doctors who give your child anesthesia are board certified in pediatric anesthesiology. This means they have extra years of training in how to take care of kids. Our child life specialists know how to help children understand their illnesses and treatments in ways that make sense for their age. Our expertise in pediatrics truly makes a difference for our patients and families.

How do you treat pyloric stenosis?

Doctors treat pyloric stenosis by making a small cut, or incision, in the thickened muscle. This opens the narrowed passageway so food can pass out of the stomach more easily. The surgery is called pyloromyotomy (pie-lor-oh-my-OTT-uh-mee).

Before the surgery, your baby will need blood tests to check for chemical imbalances caused by vomiting. Babies also need IV (short for intravenous) fluids before this surgery to replace fluid lost from vomiting. To get enough fluid, your baby may need to stay in the hospital for a day or so before surgery.

Surgery

At the time of surgery, your baby will have general anesthesia. This means we will give your child medicine to make them sleep without pain during the surgery. This operation can be performed laparoscopically or with an open technique, usually with an incision near the belly button. There are ways your surgeon can make the incision almost invisible either way. The choice of operation will be up to your surgeon.

After seeing the pylorus, the surgeon makes a small length-wise cut in the pylorus muscle. The inner lining of the passageway isn’t cut, only the muscle around it. No tissue is removed. The surgery takes 15 minutes to one hour, and your baby will be in the recovery room for another hour. Some babies will take some time to wake from anesthesia, so their time in the operating room will be longer than the actual surgery time.

After surgery

After surgery, you can expect your baby to stay in the hospital for one to two days. During this time, your baby may still vomit a little as their body adjusts to the surgery. This is normal. We will give your baby pain medicine to make them comfortable. They will also continue to get IV fluids until they can take enough formula or breast milk by mouth. Their diet will start slowly, with watered-down formula at first. The amount and strength of each feeding will be increased a little each time. As soon as your baby can eat regular full-strength formula or breast milk for several hours, they can go home.

At home, your baby will need slower feedings with more frequent burping for a few days. Then you can go back to your usual feeding routine. You’ll need to keep the incision clean and dry until it heals. The surgery team will teach you how to do this. Otherwise, you can care for your baby normally. There is no need to limit your baby’s activities.

About two to three weeks after surgery, your baby will need to see the surgeon for a follow-up visit. The surgeon will make sure the incision is healing and your child is able to eat normally.

Babies with pyloric stenosis are usually fine once they recover from surgery and are eating well. They’re at no greater risk for stomach, intestine or other problems later on than any other children.

Resources

Read more about what to expect when your child visits a clinic at Children's, has surgery here or needs to stay in the hospital. You can get practical details about topics like what to do and bring the day of surgery and who will be on your child's care team. You can also take a virtual tour of our surgery rooms and other parts of the hospital.

To learn more about this condition, you may want to visit our resource list.