Often, physiologic jaundice -- the type seen in most newborns -- does not require treatment. It will typically disappear in a few days. Doctors will test the baby's bilirubin levels during that time to make sure it has not gotten worse.

In rare cases, bilirubin levels become too high very quickly. Special blood tests will help determine the cause -- possibly an infection, a liver problem at birth, a blood problem, or a problem related to breastfeeding.