Here is what I found....
About 40 percent of young babies spit up regularly. The peak age for spitting up is 4 months.
When your baby takes in air along with his breast milk or formula, the air gets trapped in with the liquid. The air has to come up, and when it does, so does some of the liquid.
Babies take in a lot of nourishment in relation to their size, and some of them really like to eat, so sometimes they become overfilled and, well, overflow.
A newborn's digestive system isn't fully developed, either. The muscles at the bottom of your baby's esophagus, which control whether food is coming or going, may still be getting up to speed. It's no wonder your baby creates so much laundry.
at 11:57 PM on Oct. 7, 2009