Drinking alcohol while breastfeeding harms the infant

What the research found

Australian health guidance says alcohol passes into breastmilk, and the level matches the mother's blood. It can stay there for several hours. It can reduce milk flow, which may unsettle the baby and make them eat and sleep less. It can also affect how the baby's brain and spinal cord develop.

The guidance says a baby's brain keeps developing after birth, so an infant's brain is more sensitive to alcohol damage than an adult's. It says no safe level has been identified. The national alcohol guidelines say that for breastfeeding women, not drinking is safest for the baby.

A 2014 review of 41 publications found alcohol temporarily lowers milk yield by inhibiting the milk ejection reflex. It estimated babies receive about 5-6% of the mother's weight-adjusted dose. The review also noted that effects of drinking during breastfeeding have been far less examined than effects during pregnancy. A 1997 randomised trial noted earlier research found babies took in less milk after their mothers drank.

What it doesn’t mean

• The guidance does not identify a safe level of alcohol while breastfeeding. Not drinking is the safest option for your baby.
• The research on drinking during breastfeeding is more limited than for pregnancy. The clearest effects described are on milk flow and feeding, plus the guidance's concern about the developing brain.
• If you are worried about your drinking, or want advice for your situation, talk to a GP or child health nurse. Alcohol in pregnancy is a separate issue, and guidance links it to serious harm, including Fetal Alcohol Spectrum Disorder.