What to know
Despite significant efforts to prevent mix-ups, occasionally expressed breast milk from a mother is given to another mother’s child accidentally. If that happens, take steps to minimize fear and appropriately manage the situation.
Actions to take
Few illnesses are transmitted via breast milk. Instead, the unique properties of breast milk help protect infants from colds and other typical childhood viruses. Nonetheless, both families need to be notified when there is a milk mix-up. They need to know that the risk of the mix-up transmitting an infectious disease is small.
Follow these steps if there is a breast milk mix-up:
- Inform the mother whose breast milk was given to another child. Ask her:
- When was the breast milk expressed?
- How was it handled prior to being delivered to the caretaker or facility?
- Would she share information about her medication use, recent infectious disease history, and presence of cracked or bleeding nipples during milk expression?
2. Discuss the event with the parent(s) or guardian(s) of the child who was given another mother's milk:
- Inform them that their child was given another mother's expressed breast milk.
- Inform them that the risk of transmission of infectious diseases is small.
- If possible, provide the family with information on when the milk was expressed and how the milk was handled prior to its being delivered to the caretaker.
- Encourage the parent(s) or guardian(s) to notify the child's physician of the situation and share any specific details known.
Next steps after a breast milk mix-up
Potential Concerns
Exposure to human immunodeficiency virus (HIV)
Routine prenatal care in the United States includes laboratory testing for sexually transmitted infections (STIs) and HIV. Most US women living with HIV are identified prior to or during their maternity hospital stay and most have been on antiretroviral therapy (ART). For mothers with HIV on ART with a sustained undetectable HIV viral load, the risk of transmission through breastfeeding their infant is less than 1%.
Additionally, most women with HIV in the United States do not breastfeed if their viral load is detectable. So, the risk of transmission of HIV to an infant to whom a single bottle of another mother's milk was fed is very low. CDC is unaware of any evidence of transmission of HIV to a child via a single exposure to another mother's milk.
Exposure to hepatitis B and C viruses
It is very unlikely that a child would be at risk for hepatitis B or C by receiving another mother's breast milk. Hepatitis B and C cannot be spread from a woman to a child through breastfeeding or close contact unless there is exposure to blood.
Furthermore, most US infants receive one dose of the hepatitis B vaccine shortly after birth, a second dose between 1–2 months of age, and the third dose between 6–18 months of age.
Infants who have not been vaccinated, or infants whose vaccine schedule was interrupted, should be vaccinated according to the Advisory Committee on Immunization Practices' hepatitis B vaccine recommendations as soon as possible.
There is no vaccine for hepatitis C. There is also no evidence that breastfeeding spreads the hepatitis C virus.
Exposure to medications
Although many medications do pass into breast milk, most have little or no effect on infant well-being. Only a few medications should not be used when a mother is breastfeeding. Also, the risk of adverse effects from a single exposure to a medication through breast milk is very low.
Prevent Milk Mix-Ups
To help prevent milk mix-ups, childcare facilities can:
- Review and update their policies and practices for storing and handling breast milk.
- Train (or retrain) all childcare facility staff in safe storage and handling of breast milk.
- Clearly label expressed breast milk with the child's name.
- Consider strategies such as putting different colored rubber bands around the bottles for different infants or using separate bins for each infant's bottles of milk.
Learn More
- Contraindications to Breastfeeding or Feeding Expressed Breast Milk to Infants
- Breastfeeding and Vaccinations, Medications, & Drugs
- Breastfeeding and HIV
- Breastfeeding and Hepatitis B or C Infections
- Supporting Breastfeeding Families in Early Care and Education (ECE) Programs
- Storage, Handling, and Preparation of Breast Milk in Early Care and Education Programs
- Solid Foods in Early Care and Education (ECE) Tips for ECE Providers
- Warner, B.B and Sapsford, A. (2004). Misappropriated Human Milk: Fantasy, Fear, and Fact Regarding Infectious Risk. Newborn and Infant Nursing Reviews, 4(1):56-61.