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Home > Health Library > Pyloric Stenosis
Pyloric stenosis is a problem with a baby's stomach that causes forceful vomiting. It happens when the baby's pylorus, which connects the stomach and the small intestine, swells and thickens. This can keep food from moving into the intestine.
A baby may get pyloric stenosis anytime between birth and 5 months of age. Boys are more likely than girls to get it. It usually starts about 3 weeks after birth. If your baby was born early (premature), symptoms may start later.
Experts don't know what causes pyloric stenosis. It may be passed down through families.
A baby with pyloric stenosis may:
Vomiting usually starts gradually. As the pylorus becomes tighter, the vomiting may become more frequent and more forceful.
As the vomiting continues, your baby may:
Your doctor will do a physical exam and ask about your baby's symptoms. If your baby has pyloric stenosis, the doctor may be able to feel a small lump in the upper part of the belly.
In some cases your baby may need imaging tests, such as an upper GI (gastrointestinal) series or an abdominal ultrasound. Your baby also may need blood tests to see if he or she is dehydrated.
Pyloric stenosis is treated with surgery to widen the opening between the stomach and the small intestine. Surgery rarely causes problems, and almost all babies recover completely. After surgery, your baby probably won't get pyloric stenosis again.
Your baby likely will be ready to go home within 2 days after surgery. Being involved in your baby's care while he or she is in the hospital may help you feel more comfortable when you take your baby home. Talk with the doctor about how to feed your baby and what to expect. It's normal to feel nervous, but don't be afraid to hold and handle your baby.
Other Works Consulted
Greenup RA, Calkins CM (2011). Infantile hypertrophic pyloric stenosis. In CD Rudolph et al., eds., Rudolph's Pediatrics, 22nd ed., pp. 1420–1421. New York: McGraw-Hill.
Hoffenberg E, et al. (2014). Gastrointestinal tract. In WW Hay Jr et al., eds., Current Diagnosis and Treatment: Pediatrics, 22nd ed., pp. 651–691. New York: McGraw-Hill.
Hunter AK, Liacouras CA (2011). Pyloric stenosis and other congenital anomalies of the stomach. In RM Kliegman et al., eds., Nelson Textbook of Pediatrics, 19th ed., pp. 1274–1276. Philadelphia: Saunders.
Middlesworth W, Kadenhe-Chiweshe A (2006). Neonatal intestinal obstruction. In FD Burg et al., eds., Current Pediatric Therapy, 18th ed., pp. 289–293. Philadelphia: Saunders Elsevier.
Semrin MG, Russo MA (2010). Anatomy, histology, embryology, and developmental anomalies of the stomach and duodenum. In M Feldman et al., eds., Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 9th ed., vol. 1, pp. 773–788. Philadelphia: Saunders.
Current as of: August 22, 2019
Author: Healthwise StaffMedical Review: John Pope, MD, MPH - PediatricsKathleen Romito, MD - Family MedicineBrad W. Warner, MD - Pediatric Surgery, Critical Care Medicine
Current as of: August 22, 2019
Author: Healthwise Staff
Medical Review:John Pope, MD, MPH - Pediatrics & Kathleen Romito, MD - Family Medicine & Brad W. Warner, MD - Pediatric Surgery, Critical Care Medicine
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