Blood in Breast Milk

If you notice breast milk streaked with red (or pink or brown) after you have expressed your milk or after your baby has spit up some milk after a feed, you may be worried that your breast milk has blood in it.  This blood can come from one of several places, and is not usually serious.

Common causes of blood in breast milk can include:

  • When a damaged nipple opens up and the crack bleeds as baby sucks
  • When ducts and milk making cells grow and stretch in the first few days after birth (rusty pipe syndrome, see below)
  • Intraductal pailloma; a small benign growth on the milk duct lining which bleeds
  • Fibrocystic changes
  • Breast or nipple damage from rough handling

Blood in breast milk

The Australian Breastfeeding Association advises checking with your doctor if any blood is noticed in breast milk to be on the safe side but in most cases it will not represent a serious condition. Blood in breast milk may appear as bright red, pink, black, olive green, chocolate brown colour (ABA, 2013).

Can I feed my baby breast milk that has blood in it?

Jack Newman, Canadian paediatrician and breastfeeding expert says that although blood will cause a baby to spit up more, and digested blood may show up in his bowel movements “this is not a reason to stop breastfeeding the baby” (Myths of Breastfeeding).

Breastfeeding author and lactation consultant Nancy Mohrbacher says in Breastfeeding Answers Made Simple 2010 p 702 “it is fine to continue breastfeeding and the bleeding will not harm your baby”. She points out that normal milk and colostrum come in a variety of different colours including blue, green, brownish, yellow, gold and clear.

Spitting up blood or blood in baby’s poop

If your baby has drunk a lot of blood stained breast milk they might have very dark poop or may spit up blood-stained milk. The blood can form a large clump in the stomach which might look like a lot of blood when spit up. In these situations always check with your health professional for immediate medical advice (ABA, 2013).

Cracked nipples

If the cause of the blood in your breast milk is definitely due to damaged nipples, see our article on causes of sore nipples or contact your IBCLC lactation consultant for help with positioning and latching your newborn baby.

What is rusty pipe syndrome?

This is the name given to small amounts of blood seen in the milk during the first week or so after birth. It’s thought to be due to extra blood flow to the breast and fast development of glandular tissue. This is discussed in Dr Jack Newman’s Guide to Breastfeeding:

It is not surprising that sometimes blood vessels leak a little blood into a duct, and it then comes out of the nipple. It is not dangerous for the mother or the baby. Sometimes when a baby swallows blood he may spit it up because it irritates his stomach, but it really does him no harm. The bleeding usually disappears by 7 to 10 days after birth. Breastfeeding must not be interrupted.

If bleeding carries on after baby is a week old or if bleeding happens at a later stage than the first week, continue breastfeeding but always check with your doctor (Newman, 2013).

Other causes of pink breast milk

Food pigments may colour breast milk

Sometimes a food in mother’s diet may colour her breast milk pink e.g. beetroot. In Baby Poop: What Your Pediatrician May Not Tell You, author Linda Palmer says that the pigments from natural foods such as beets are usually good antioxidants and don’t need to be avoided. She adds that if if the pigment has coloured the milk this means it has passed through mother’s system undigested and will probably go through baby’s system the same way.

Bacteria can colour milk pink

Thomas Hale describes another possible cause of pink/red milk that may not be blood; a bacteria called Serratia marsescens. Although S. marsescens is normally harmless and commonly found in children’s gastrointestinal tracts it can be the cause of infection, especially for premature babies.

It is unlikely that a baby feeding directly from the mother’s breast will consume enough bacteria to cause disease. However improper handling of breast milk may allow the bacteria to multiply to numbers capable of producing disease. Refrigeration of breast milk and breastfeeding equipment is usually sufficient to prevent Serratia from multiplying and generating pigment.

Hale advises never feeding your baby pink-red discoloured breast milk until you have been cleared by a doctor. See the full article for further information.

Expressed breast milk and pump

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