Signs of Pyloric Stenosis in Babies
The short answer
Pyloric stenosis is a rare condition (affecting about 3 in 1,000 babies) where the stomach outlet thickens, blocking food from entering the small intestine. The hallmark sign is forceful, projectile vomiting after feeds starting around 3-5 weeks of age, with baby seeming hungry immediately after. It requires surgical correction but has an excellent prognosis when treated.
By Age
What to expect by age
Pyloric stenosis symptoms rarely appear in the first two weeks of life. If your newborn is vomiting, it's more likely to be normal spit-up, reflux, or feeding issues like overfeeding or swallowing air. However, if you notice true projectile vomiting (shooting several feet) at this age, contact your pediatrician promptly.
This is the most common age for pyloric stenosis to appear. Symptoms typically start gradually: first occasional vomiting after feeds, then becoming more frequent and forceful. The vomiting is projectile (shoots out with force, not just dribbling), happens shortly after most feeds, and doesn't contain bile (it's usually just milk). Baby seems hungry and eager to feed again right after vomiting.
While less common, pyloric stenosis can develop up to 3 months of age. If your older baby suddenly develops forceful, projectile vomiting after a period of normal feeding, don't dismiss it. Other signs at this age include fewer wet diapers, weight loss or poor weight gain, constipation (small, infrequent stools), and appearing dehydrated. Sometimes you can see wave-like contractions across baby's belly after feeding.
Pyloric stenosis is extremely rare after 3 months. If your baby has projectile vomiting at this age, other causes are more likely, such as gastroenteritis, food intolerance, or reflux. Still, any pattern of forceful vomiting deserves medical evaluation.
What Should You Do?
When to take action
- Occasional spit-up that dribbles out, even if it seems like a lot
- Vomiting once or twice that doesn't create a pattern
- Baby continues to gain weight appropriately
- Plenty of wet diapers (6+ per day)
- Baby seems content between feeds
- Vomiting is becoming more frequent or more forceful
- Baby seems hungrier than usual despite feeding well
- You're concerned about the force or frequency of vomiting
- Slightly fewer wet diapers than usual
- Projectile vomiting after most or all feeds
- Baby isn't gaining weight or is losing weight
- Fewer than 4-6 wet diapers in 24 hours
- Baby seems lethargic, has sunken soft spot, or dry mouth
- You can see wave-like movements across baby's belly after feeding
- Vomit is green, yellow, or contains blood
Sources
Related Resources
Related Digestive Concerns
My Baby's Belly Looks Swollen
A rounded, slightly protruding belly is completely normal in babies and toddlers due to immature abdominal muscles and their proportionally larger organs. However, if the belly becomes suddenly swollen, feels hard and tight, or is accompanied by pain, vomiting, or changes in bowel movements, it needs medical evaluation as it could signal gas buildup, constipation, or rarely, something more serious.
My Baby Has an Anal Fissure (Blood When Pooping)
A small streak of bright red blood on the surface of your baby's stool or on the diaper is most commonly caused by an anal fissure, which is a tiny tear in the skin around the anus from passing hard stool. Anal fissures are very common in babies and toddlers and usually heal on their own with simple measures like keeping stools soft. While this is rarely serious, any blood in your baby's stool should be mentioned to your pediatrician.
My Baby Eats Non-Food Items (Pica)
It is completely normal for babies and young toddlers to explore by putting objects in their mouths. True pica, which is the persistent eating of non-food substances, is uncommon before age two and may be linked to iron deficiency or developmental factors. If your child repeatedly seeks out and eats non-food items past the typical mouthing stage, it is worth discussing with your pediatrician.
Baby Excessive Gas After Starting Solids
Increased gas after starting solid foods is completely normal and expected. Your baby's digestive system is encountering new proteins, fibers, and sugars for the first time and needs time to adapt. The gut bacteria are also diversifying, which naturally produces more gas. This typically improves within a few weeks as the digestive system adjusts to each new food.
My Baby Gulps Air While Feeding
Swallowing some air during feeding is normal for all babies, but excessive air gulping can lead to gas, hiccups, and spit-up. Common causes include fast milk flow, poor latch (if breastfeeding), bottle nipple flow that's too fast or slow, and crying before feeds. Simple adjustments to feeding position, pacing, and equipment can usually help reduce air intake significantly.
Baby Poop Color Changes with Solids
Dramatic changes in poop color after starting solids are completely normal and expected. What your baby eats directly affects stool color - carrots may turn poop orange, spinach makes it green, beets can make it reddish, and blueberries can turn it dark blue-black. As long as your baby is comfortable and the stool is not white, black (tarry), or bright red with blood, these color changes are harmless.