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June 14, 2013

What is Jaundice

Newborn jaundice is when a baby has high levels of bilirubin in the blood. Bilirubin is a yellow substance that the body creates when it replaces old red blood cells.

Q: What is Jaundice? Why does it happen?

Newborn jaundice is when a baby has high levels of bilirubin in the blood. Bilirubin is a yellow substance that the body creates when it replaces old red blood cells. The liver helps break down the substance so it can be removed from the body in the stool. High levels of bilirubin makes your baby's skin and whites of the eyes look yellow. The color sometimes begins on the face and then moves down to the chest, belly area, legs, and soles of the feet.  Sometimes, infants with significant jaundice have extreme tiredness and poor feeding.

It is normal for a baby's bilirubin level to be a bit higher after birth. Prior to birth, the placenta removes bilirubin from the baby's body. After birth, the baby's liver starts doing this job. This can take a while. Most newborns have some yellowing of the skin, or jaundice. This is called “physiological jaundice.” It is harmless, and usually is worst when the baby is 2 – 4 days old. It goes away within two weeks and doesn't usually cause a problem. 

Two types of jaundice may occur in newborns who are breast fed. Both are usually harmless. “Breastfeeding jaundice” is seen in breastfed babies during the first week of life, especially in babies who do not nurse well or if the mother's milk is slow to come in.  “Breast milk jaundice” may appear in some healthy, breastfed babies after day 7 of life. It usually peaks during weeks 2 and 3. It may last at low levels for a month or more. It may be due to how substances in the breast milk affect how bilirubin breaks down in the liver.

Severe newborn jaundice may occur if your baby has a condition that increases the number of red blood cells that need to be replaced in the body, such as abnormal blood cell shapes, blood type mismatch between the mother and the baby, bleeding underneath the scalp (cephalohematoma) caused by a difficult delivery, higher levels of red blood cells (which is more common in small-for-gestational-age babies and some twins), infection, and lack (deficiency) of certain important proteins, called enzymes.   

By Dr. Lachin Hajhosseini, family physician, ThedaCare Physicians-Appleton North.