The pylorus is the muscle that closes the stomach off from the intestine and keeps food in the stomach. Stenosis means closed off. Pyloric stenosis is thickening of the pylorus muscle that partly or fully blocks food from passing out of the baby’s stomach into the intestine.
Babies with pyloric stenosis eat well but throw up forcefully soon after eating
Pyloric stenosis usually happens when a baby is 1 or 2 months old
Babies can become dehydrated (have too little fluid in their bodies) and not get enough nutrients
To tell if your baby has pyloric stenosis, doctors do an ultrasound
Doctors do surgery to cut and loosen the thickened muscle
There's a higher risk of pyloric stenosis in:
Babies with pyloric stenosis are hungry, eat well, and then forcefully throw up (projectile vomiting) after eating. Unlike babies who throw up because they're sick, babies with pyloric stenosis want to eat and drink right away after they throw up.
Sometimes, babies throw up so much they:
Usually, babies are still able to absorb liquids enough that they don't become dehydrated. However, they may lose a lot of weight and look very thin before doctors figure out what's wrong.