Physiological jaundice (icterus neonatorum)

At about 2 days of age, parents may notice that their newborn is a yellowish colour. This is quite normal and results from the breakdown of the excess red blood cells that the child needed when they were in utero. As the child breaths following delivery, it no longer has any need of these red blood cells, so they break down leading to high serum bilirubin levels and the consequent yellow colour. This type of jaundice should not be confused with pathologic jaundice which occurs within 24 hours of birth and may be indicative of ABO or rhesus incompatibilities.