Hyperbilirubinemia and Jaundice

Hyperbilirubinemia is a condition in which there is too much bilirubin in your baby’s blood.

When red blood cells break down, a substance called bilirubin is formed. Babies are not easily able to get rid of the bilirubin, and it can build up in the blood and other tissues and fluids of your baby’s body. This is called hyperbilirubinemia. Because bilirubin has a pigment or coloring, it causes a yellowing of your baby’s skin and tissues. This is called jaundice.

Depending on the cause of the hyperbilirubinemia, jaundice may appear at birth or at any time afterward.

What causes hyperbilirubinemia?

During pregnancy, the placenta excretes bilirubin. When your baby is born, your baby’s liver must take over this function. There are several causes of hyperbilirubinemia and jaundice, including:

  • physiologic jaundice: occurs as a “normal” response to your baby’s limited ability to excrete bilirubin in the first days of life
  • breast milk jaundice: about 2 percent of breastfed babies develop jaundice after the first week
  • breastfeeding jaundice: occurs in some baby’s in the first week due to low intake or dehydration
  • jaundice from hemolysis: a condition that results from the breakdown of red blood cells due to hemolytic disease of the newborn (Rh disease), polycythemia, or hemorrhage
  • inadequate liver function: due to infection or other factors

Who is affected by hyperbilirubinemia?

About 60 percent of term newborns and 80 percent of premature babies develop jaundice. Infants of diabetic mothers and of mothers with Rh disease are more likely to develop hyperbilirubinemia and jaundice.

Why is hyperbilirubinemia a concern?

Although low levels of bilirubin are not usually a concern, large amounts can circulate to tissues in the brain and may cause seizures and brain damage. This is a condition called kernicterus.

What are the symptoms of hyperbilirubinemia?

Symptoms may include:

  • yellow coloring of your baby’s skin (usually beginning on the face and moving down the body)
  • poor feeding or lethargy

How Boston Children’s approaches hyperbilirubinemia

Children and adolescents with all forms of non-malignant blood disorders, including anemias, bleeding problems, blood clots, platelet disorders, and red and white blood cell disorders, are treated through our Pediatric Hematology service. If necessary, Children’s also offers access to the largest pediatric stem cell transplantation program in New England.