Pyloric stenosis


Pyloric stenosis, also known as hypertrophic pyloric stenosis (HPS), is an uncommon condition in infants, this prevents food from reaching the small intestine. This is a condition that impacts the pylorus of your infant. When the pylorus becomes thicker and narrower, it restricts the passage of food.

Pylorus is the muscular sphincter of the stomach and small intestine that normally keeps food in the stomach until it is prepared to move on to the next stage of digestion. Food cannot pass through the unusually thickened and enlarged pylorus muscles in pyloric stenosis, which prevents food from reaching the small intestine.

Pyloric stenosis can cause forceful vomiting and dehydration. Because as they often vomit, numerous infants have trouble gaining weight. Infants who have pyloric stenosis may appear to be constantly hungry

Treatment for this condition is surgical procedure


Pyloric stenosis symptoms often show up 3 to 5 weeks after delivery. Pyloric stenosis in infants older than three months is rare. Signs and symptoms may include the following:

  • Projectile vomiting: The infant can throw up forcefully, projecting formula or breast milk up to a few feet away. Initially, vomiting might be minor. However, when the pylorus opening narrows over time, it worsens. Sometimes, blood may be present in the vomit.
  • Dehydration: There’s a chance the baby will cry without tears, or it seems that the baby is weak. They could find that they have to change fewer wet diapers or diapers that aren’t as wet as they anticipated.
  • Persistent hunger: Pyloric stenosis infants might want food immediately after throwing up.
  • Stomach contractions: Before vomiting but shortly after a feeding, the infant may experience wavelike contractions that ripple across the upper abdomen. The digestion process known as peristalsis. In an effort to push food through the constricted pylorus, the stomach muscles contract. 
  • Underweight: Pyloric stenosis occasionally results in weight loss and might prevent a newborn from gaining weight.
  • Bowel movement changes: Infants with pyloric stenosis may have constipation because the disease prevents food from reaching the intestines.

Most infants seem to be generally healthy. Before newborns become severely malnourished or dehydrated, parents might not realize anything is wrong. When their skin and eye whites turn yellow, babies may also begin to develop jaundice.

Seek medical attention if the infant is experiencing any of the signs and symptoms especially when the infant frequently vomits after feeding


Although the exact causes of pyloric stenosis remain unknown, environmental and genetic factors may be involved. Pyloric stenosis often does not exist at birth and likely appears later

Risk factors

The risk for pyloric stenosis is increased by the following factors

  • Family history: Certain families have a greater incidence of this condition, according to studies. A biological family history of the problem runs in around 15% of newborns with pyloric stenosis
  • Gender: Boys are more likely than girls to have pyloric stenosis, particularly firstborn children
  • Race: Children who are white and Hispanic are more likely to develop pyloric stenosis
  • Premature birth: Premature births are more likely to result in pyloric stenosis than fullterm births
  • Smoking: Babies who had mothers who smoked throughout pregnancy are more at risk. The risk of pyloric stenosis might almost double as a result of this habit
  • Antibiotic use: Babies who get certain antibiotics in the first few weeks of life, such as erythromycin to treat whooping cough, are more likely to develop pyloric stenosis. In addition, pyloric stenosis risk may be higher in offspring of mothers who used certain antibiotics in the final trimester of pregnancy.
  • Bottlefeeding: According to certain research, bottle feeding an infant rather than nursing may increase their likelihood of developing pyloric stenosis. It is unclear if the higher risk is linked to formula or the process of bottle-feeding because most of the participants in these trials utilized formula rather than breast milk.