In most cases, infants with jaundice aren't in any serious trouble. In fact, the condition is pretty common in newborns, especially those born before the 36th week of pregnancy [source: Mayo Clinic]. This is because the liver isn't fully developed enough to properly treat the bilirubin as needed; treatment often isn't necessary. As long as the infant is fed frequently and monitored for jaundice during the first few days of life, the risk of developing a more serious condition is quite low [source: Kaneshiro]. Jaundice usually occurs within two to three days of the baby's birth [source: Mayo Clinic].
Although doctors often can base their diagnosis on the baby's appearance, they can also find jaundice by testing the infant's blood or by using a special light to inspect the skin [source: Mayo Clinic].
Babies who aren't born with jaundice can develop it for other reasons. Like in serious adult cases, this type of jaundice normally is caused by an underlying complication like internal bleeding, blood infection, liver malfunction or abnormal red blood cells [source: Mayo Clinic]. In these situations, the yellowing of the skin can show up much earlier or much later in life than normal infant jaundice.
To read about how jaundice affects adults, go to the following page.