Babies commonly spit up since the sphincter at the top of the stomach is often loose. In healthy babies who are growing well, the spit-up is mostly milk, rather than stomach acid. On average spitting up peaks at 4 months and is over by about 7 months of age, though it can take longer. To help reduce spitting up, burp the baby several times during and after feeding.
Update Date 8/2/2011
Updated by: Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.