Nearly all babies spit up to some degree. Occasionally, though, a baby seems to vomit so much that parents wonder if something is wrong.
Persistent spitting up in babies is called reflux (also called gastroesophageal reflux or GER.) Reflux is never concerning in an otherwise normal baby who is growing and developing normally. It will sometimes seem that a baby vomits more than he eats, and may seem amazing that he grows or gains weight at all! These "happy spitters" do quite well, and are chubby more often than scrawny. Most show significant improvement by 6 months of age, and almost all are better by their first birthday.
In our experience, most "spitty babies" are formula fed. This is because formula flows much faster from a bottle than human milk does from the breast. It's a lot easier to "overeat" when the baby doesn't have to work to get the milk. Babies also don't "know when to say when." An infant's stomach is not much bigger than his two fists together; babies will try to eat more, resulting in vomiting. The baby will then be hungry again, causing a second rapid feeding (and often more vomiting.)
Reflux can be very smelly. Many parents are concerned when they see nasty-smelling curdled milk in their child's vomit. However, this is what milk mixed with stomach acid looks like; it's not a sign of something strange. Reflux can indeed be messy, but it's not harmful to an otherwise normal baby. If reflux bothers you, here are some things you can do to help it:
Feed your baby in the upright position.
Offer your baby smaller feedings that are more frequent. This is the single biggest change you can make to help reduce spitting up. For example, most one month olds spit up if they take 4 oz at a time every four hours. The same baby will probably be much less "spitty" with 2 oz every two hours - which is still the same total amount of milk in a 24 hour period. Most newborns can only take an ounce or two at a time; most four-month-olds get "spitty" beyond 4 ounces at a time.
Elevate the head of your baby's bassinet or crib at an angle of about 15 degrees. This gets gravity on your side. (Let your baby lie flat or stand up; a seated position such as in a car seat can actually cause more reflux.)
Burp your baby well in the middle of and after feedings. "Barracuda babies" who ravenously take a complete feeding in 10 minutes swallow lots of air with their milk.
Try a different type of bottle. There are new "airless" bottles that reduce the amount of air babies swallow with feedings, available at some of our local pharmacies. These bottles also result in slower milk flow, helping infants to feed slower overall.
Add a teaspoon of rice cereal to a bottle to thicken the feedings.
What if these things don't work?
Let us know if the above suggestions don't work. Sometimes we can recommend other changes if reflux persists, like prescription medication. Vomiting is rarely caused by formula intolerance, and so we don't usually recommend changing formulas simply for persistent spitting up.
When is spitting up worrisome?
Extremely forceful ("projectile") vomiting. Although seen in many normal children, it can be the sign of severe blockage if it happens more than once.
Dehydration, as seen by decreased saliva, tears, and urine (see our information sheet on dehydration.)
Weight loss or minimal weight gain in a child under the age of 1. Ask us if you are concerned about your baby's weight gain.
Peculiar vomit, containing bile (bright green) or blood (red or brown.)
Associated with other symptoms which are themselves concerning, like severe belly pain or distension, wheezing, profuse diarrhea, and/or severe skin rashes. These should be reported to your doctor immediately.