Breast Milk Jaundice: How It Differs From Early Feeding Jaundice

A little yellow tint in the first days after birth is very common. But what if your breastfed baby is still yellow at 2 or 3 weeks old, even though they’re feeding well and putting on weight? That’s often breast milk jaundice, a usually harmless condition that can look worrying.

It’s easy to mix up with another kind of jaundice that happens when a baby isn’t getting enough milk early on. The two have different causes, different timing and different fixes. Here’s how to tell them apart, what the American Academy of Pediatrics (AAP) recommends and which signs mean you should call your baby’s doctor.

What is newborn jaundice?

Jaundice is yellowing of the skin and the whites of the eyes caused by bilirubin, a yellow substance made when the body breaks down old red blood cells. A newborn’s liver is still learning to clear bilirubin, so it builds up for a few days.

According to MedlinePlus, it’s normal for babies to look a little yellow between days 1 and 5, with color usually peaking around day 3 or 4. Most cases are mild. Very high bilirubin, though, can rarely damage the brain, which is why every newborn is checked.

Two kinds of jaundice linked to breastfeeding

	Early feeding jaundice (suboptimal intake)	Breast milk jaundice
When it shows up	First few days	After the first week
Cause	Baby isn’t getting enough milk yet	Factors in breast milk affect how bilirubin is processed
How the baby is doing	Often extra weight loss, fewer diapers, sleepy feeds	Feeding well, gaining weight, content
What helps	More frequent, effective feeds; sometimes supplements	Usually nothing beyond monitoring
How long	Improves as intake improves	Can last weeks, sometimes up to about 3 months

Early feeding jaundice (suboptimal intake hyperbilirubinemia)

This used to be called “breastfeeding jaundice,” and the AAP’s 2022 guideline now frames it as suboptimal intake. It isn’t caused by breast milk itself but by a baby not getting enough of it in the first days, often while milk is still coming in or when the latch isn’t working well. Less milk means fewer stools, and stools are how babies get rid of much of their bilirubin.

The AAFP’s summary of the AAP guideline notes it peaks around days 3 to 5 and often goes along with more weight loss than expected. Helping your baby feed more often and more effectively is the main fix. Our guide on when breast milk comes in explains what to expect in those first days.

Breast milk jaundice

Breast milk jaundice appears after the first week in a breastfed baby who is otherwise healthy, feeding well and gaining weight. MedlinePlus explains it’s likely caused by substances in breast milk that increase how much bilirubin is reabsorbed from the gut and slow how the liver breaks it down. It may run in families.

According to the AAFP summary, it can persist for up to about three months. It usually fades on its own without treatment. Because other conditions can also cause jaundice that lingers, doctors treat breast milk jaundice as a diagnosis to confirm, not to assume.

What the AAP 2022 guideline says

In 2022 the AAP published a revised guideline for managing jaundice in babies born at 35 weeks or later. Key points for breastfeeding families:

• Breastfeeding support matters. The guideline highlights support starting in the first hour after birth and continuing through the first weeks. Feeding at least 8 times every 24 hours is encouraged; HealthyChildren suggests 8 to 12 times a day in the first days.
• No water or sugar water. Giving water or dextrose water to prevent or lower jaundice is not recommended.
• Every newborn gets a bilirubin check before going home from the hospital, with follow-up timing based on how close the level is to the treatment threshold.
• Treatment thresholds are a bit higher than before. Newer research suggests bilirubin becomes harmful at higher levels than once thought, so phototherapy now starts at slightly higher levels than under the 2004 guideline.
• Lingering jaundice needs a test. If a breastfed baby is still jaundiced at 3 to 4 weeks (or a formula-fed baby at 2 weeks), the guideline recommends measuring total and direct (conjugated) bilirubin to check for liver problems such as cholestasis.

The AAP lists this guideline as current through August 2027.

Keep breastfeeding

For most babies with either kind of jaundice, breastfeeding should continue. MedlinePlus advises against stopping, because babies need breast milk. Feeding often, with unlimited time at each breast, can help bring bilirubin down. Our guide on how often to breastfeed a newborn covers normal feeding patterns.

Sometimes a doctor may suggest formula or expressed milk top-ups, for example if your baby has lost a lot of weight or is having phototherapy. MedlinePlus notes that a brief formula trial is occasionally used but isn’t always necessary. If supplements are suggested, ask how to pump so your milk supply stays protected. Our breast milk intake calculator gives typical amounts by age and weight.

Signs your baby is getting enough milk

• Regular swallowing during feeds
• Wet and dirty diapers increasing day by day in the first week (our baby poop color chart shows typical counts and colors)
• Weight loss slowing and then regaining toward birth weight

When to call your baby’s doctor

HealthyChildren and MedlinePlus advise calling your baby’s doctor if:

• Jaundice appears in the first 24 hours after birth (this needs a bilirubin test right away)
• The yellow color is getting deeper or spreading to the belly, arms or legs
• The whites of the eyes look yellow
• Your baby is hard to wake, very fussy or not feeding well
• Your baby has fewer wet or dirty diapers than expected
• Jaundice lasts beyond 4 weeks in a mostly breastfed baby (or 2 weeks if formula-fed); the AAP guideline advises a blood test at 3 to 4 weeks

If your baby is very hard to wake or won’t feed at all, don’t wait for an appointment: call right away or seek urgent care.

If latch or milk transfer is part of the problem, an IBCLC can help. Find support on our breastfeeding support page, and see related guides in our Common challenges hub.