People who are lactating are able to drink alcohol. Alcohol passes into human milk, and the level in human milk is the same as the blood alcohol level. As the blood alcohol declines hours after the last drink, the alcohol level in the milk declines as well.

The alcohol level in milk peaks at 30-60 minutes after an alcoholic beverage. Eating while drinking alcohol can reduce gastrointestinal absorption of alcohol, thereby reducing the amount of alcohol that passes into the milk.

Nursing or pumping within 1 hour before drinking alcohol can also reduce the amount of alcohol in the milk.

It is advised to limit alcohol intake to 1 serving a day (5 oz of wine, or 12 oz of beer, or 1.5 oz of hard liquor) and drink the beverage over 1 hour to keep the peak level low. This is unlikely to cause short or long term problems for the infant.

Moderate (2+ drinks a day) may decrease the infant’s milk take, cause infant agitation, and poor sleep patterns.

Heavy alcohol use can reduce milk production, with 5 drinks or more causing difficulty with milk let-down. Chronic alcohol use may be unsafe for the breastfed infant, possibly having a negative impact on infant growth and development.