Jaundice is caused by too much bilirubin in the blood, which gives your baby’s skin and the whites of his eyes a yellowish tinge. A baby is born with excess red blood cells which he needs in the womb. After birth, the liver immediately starts working to break down these red blood cells and excretes the yellow-coloured leftover product, bilirubin. Newborns often produce more bilirubin than their immature livers can handle. As a result, bilirubin builds up in the blood and leads to the yellowish tinge known as newborn or physiologic jaundice.
Yellowing usually begins on the second or third day of life and starts reducing when the baby is a week or 10 days old. (In prem babies it starts later and lasts longer.) Jaundice is more likely to occur in boys, in babies who lose a lot of weight straight after delivery, in babies with diabetic mothers and in babies born via induced labour.
Jaundiced babies will sometimes be kept in hospital for a few extra days for observation and treatment, such as phototherapy under an ultraviolet lamp. Occasionally there is a rapid increase in bilirubin, indicating that the jaundice may be abnormal or pathologic.