What is Breast Milk Jaundice?

Medically Reviewed by Dan Brennan, MD on September 04, 2023
Written by WebMD Editorial Contributor
4 min read

Breast milk jaundice is a type of jaundice that occurs in babies when breastfeeding. It's a common condition in infants and can persist for more than three weeks after a baby is born and breastfeeding. It can resolve by itself without having to discontinue breastfeeding and can go on for eight to 12 weeks before resolving. Roughly 60% to 80% of all newborns can have some degree of jaundice.

Jaundice is when there is too much bilirubin in the blood. When this happens in a baby their eyes and skin develop a yellow coloring. Bilirubin is a yellow substance that is produced after the liver breaks down red blood cells. This is a normal process. However, jaundice occurs when the liver is not breaking down bilirubin fast enough.

Normally the processed bilirubin would be transported to the intestines and removed through the stool. In jaundice, the excess bilirubin is reabsorbed into the baby’s blood. It is then deposited into different body parts including mucus membranes, the skin, and muscles.

Breastfeeding a child with jaundice. Breastfeeding provides calories and hydration for the infant while improving the mother’s milk supply. Hydration reduces the levels of bilirubin in the baby’s body. This means that it might be beneficial for a baby with jaundice. In some cases, breastfeeding may be interrupted for 12 to 48 hours to allow diagnosis of breast milk jaundice.

Many preterm newborns will have elevated bilirubin levels in the first weeks after birth. This is because:

  • Their red blood cells have a short lifespan
  • Newborns sometimes have delayed passage of meconium (first poop), thus, bilirubin is reabsorbed in the intestines
  • A newborn baby’s liver is not yet fully developed to metabolize bilirubin fast

Most newborns will have physiologic jaundice which is considered harmless.

Currently, the exact cause of breast milk jaundice is unknown. However, it is believed that it may be caused by a substance in breastmilk that prevents the liver from breaking down bilirubin. This type of jaundice is genetic. 

Your baby might be more likely to get jaundice if:

  • They are born premature — the livers of babies born prematurely are not yet fully developed to get rid of bilirubin.
  • They are not getting enough breast milk — this may happen during the first days of life when the baby has trouble breastfeeding.
  • They are breastfeeding — breast milk may prevent the liver from getting rid of bilirubin fast enough.
  • The baby has a different blood type from the mother — this causes the mother’s body to produce antibodies that attack the baby’s red blood cells.
  • The baby is born with a lot of red blood cells — the more red blood cells present, the more bilirubin.
  • They have a genetic problem making their red blood cells fragile — fragile red blood cells mean that more of them will die quickly, thus, more bilirubin levels.

The most obvious sign of jaundice is a yellow coloration of the skin and eyes. The yellow color will start to appear on the face followed by the chest, stomach, and then the legs. Other symptoms that may show if bilirubin levels continue to rise include sleepiness and troubled feeding. Your baby may also start acting fussy or sloppy as the situation gets worse.

It can be hard to spot the yellow coloration on your child’s skin especially if they have dark skin. If you find yourself in this situation, apply some pressure on your baby’s forehead or nose using your finger. If your baby has jaundice you will see the yellow color on their skin when you lift your finger.

Sometimes things may look more serious and you might have to call your doctor. These times include:

  • When your baby is not feeding well
  • When they start looking or acting sick
  • If the baby is acting sleepier than usual
  • When you notice the jaundice is getting worse

Diagnosis. The doctor makes a diagnosis of jaundice after examining your baby for yellow coloration of the skin and eyes. They may also do a blood test to check the bilirubin levels in the blood. A light machine may also be used to measure bilirubin in the skin.

Treatment of breast milk jaundice. As mentioned earlier, breast milk jaundice will go away by itself. This means that you do not have to seek treatment unless your child’s bilirubin levels get too high. Treatment should occur if the bilirubin levels go higher than what the American Academy of Pediatrics (AAP) phototherapy guidelines recommend.

Treatment of breast milk jaundice also depends on:

  • Your baby’s age
  • If the baby was born early
  • The rate at which bilirubin levels are rising
  • How your baby is feeding

Your baby’s jaundice may be treated using:

  • Phototherapy: This involves putting the baby under a light that helps the bilirubin leave the body.
  • Fluids: Hydration helps reduce bilirubin levels.
  • Immunoglobulin: This is given by injection into the vein for babies who have blood type incompatibilities and can reduce the need for exchange transfusion.
  • Exchange blood transfusion: This involves replacing the baby’s blood with a transfusion when their bilirubin levels become too high.

There is not much to worry about if your newborn baby gets jaundice. The condition is easily treatable with proper management and monitoring. It is important to understand the best way to breastfeed as it can help your baby recover from jaundice.