Breast milk jaundice is persistently high levels of bilirubin in a newborn's blood caused by certain substances found in breast milk. Bilirubin is a yellow-colored fluid that forms when red blood cells break down.

If jaundice occurs or persists past the first week of life in an otherwise healthy and thriving breast-fed infant, the condition is called "breast milk jaundice." It is probably caused by factors in the breast milk that blocks certain proteins in the liver that break down bilirubin.

Breast milk jaundice tends to run in families. It occurs equally often in males and females and affects approximately 0.5% to 2.4% of all newborns.

Jaundice causes the skin and parts of the eyes to turn a yellow color. Breast milk jaundice is prolonged jaundice in an otherwise healthy, breast-fed baby, which develops after the first week of life and continues up to the sixth week of life.

Laboratory tests that may be done include:

• Bilirubin level (total and direct)
• Complete blood count
• Blood smear to look at blood cells
• Reticulocyte count to look at slightly immature red blood cells
• Blood typing

In some cases, a blood test to check for glucose-6-phosphate dehydrogenase (G6PD) may be done. G6PD is a protein that helps red blood cells work properly.

Treatment will depend on the baby's bilirubin level. Often, this level is relatively low (less than 20 mg/dL). Sometimes no specific treatment is needed other than close followup.

More frequent nursing (up to 12 times a day) will increase the baby's fluid levels and can cause the bilirubin level to drop.

If the bilirubin level is more than 20 mg/dL, different treatment options are available. The mother can stop nursing for 24 to 48 hours, which will cause the bilirubin level to rapidly drop. During that time she can express the milk or pump her breasts (to maintain her comfort and the flow of milk) while feeding the baby formula. In most cases, when nursing is restarted the bilirubin will not return to previous levels.

The baby may need to stay in the hospital to receive treatment if the bilirubin level is greater than 20 mg/dL.

Other measures such as phototherapy (bili lights) may be used in the hospital for a short period of time. However, home phototherapy options are available.

Fluids, given through a vein, can also help increase the baby's fluid level and help lower bilirubin levels.

Full recovery is expected with appropriate monitoring and treatment.

With appropriate treatment, there are usually no complications. However, failure to receive timely and proper medical care can have severe consequences, since high bilirubin levels can be harmful to the baby's brain and other organs.

Call your health care provider immediately if you are breast feeding your baby and the baby's skin or eyes become yellow (jaundiced).

Breast milk jaundice cannot be prevented. When the condition occurs, it is very important to recognize the baby's yellow color as early as possible and have bilirubin levels checked right away to make sure that there are no other liver problems.

Breast feeding jaundice can be limited by making sure your baby is getting enough breast milk. Give your baby unlimited time at each breast, and feed approximately 10 to 12 times per day starting the first day of life. Get help from a lactation consultant or your doctor as soon as possible if you have any difficulty.