How Long Does Alcohol Stay In Breastmilk?

While the message about drinking while you're pregnant is pretty clear—according to the Centers for Disease Control and Prevention (CDC), it can be seriously harmful to babies—the message about drinking alcohol while breastfeeding is less precise.

How Much Alcohol Is Too Much in Breastmilk?

Drinking while nursing may not be illegal, but experts say large amounts of alcohol can be harmful to a breastfeeding baby. So are smaller amounts safe? And if so, how much is too much? That's less clear.

"It's definitely gray," Catherine Herway, MD, a maternal-fetal medicine specialist with CrystalRun Healthcare in Middletown, NY, told Health. There just aren't enough good-quality studies to give us the full picture, added Dr. Herway.

According to the National Institute of Health (NIH), while some evidence indicates that a baby's growth and motor function may be negatively impacted by one drink or more daily, other studies have not confirmed these findings.

Breastfeeding parents of newborns less than three months old should be extra careful about drinking, as the baby's brain is still developing and very vulnerable, said Beth Conover, a nurse practitioner at the University of Nebraska Medical Center in Omaha.

According to the CDC, exposure to alcohol above moderate levels (defined as up to one standard drink per day) through breast milk could be damaging to an infant's development, growth, and sleep patterns. In addition, the CDC points out, that this level of alcohol consumption could impair a parent's judgment and compromise the safety of the child. Evidence from the NIH shows that more than two drinks daily appear to decrease the length of time that infants are breastfed.

A 2018 study published in Pediatrics found mental development issues in children who had been exposed to alcohol through breast milk: At ages 6 and 7, these children did not perform as well as other children on reasoning tests.

The American Academy of Pediatrics (AAP) states that consuming alcohol of any kind may decrease the amount of milk your baby drinks.

Can Alcohol Help With Breastfeeding?

Unfortunately, it's an old wive's tale that a small amount of alcohol can actually help milk letdown or the release of milk. In fact, the CDC says that higher levels of alcohol consumption can interfere with letdown while maternal alcohol levels are high. While some people believe that drinking beer will increase your milk supply, the AAP emphasizes that drinking beer does not increase your milk supply. In Advances in Experimental Medicine and Biology, researchers noted that polysaccharides from barley and hops are responsible—so non-alcoholic beer has the same effect.

That said, there are ways to drink responsibly without endangering your baby. Here are three things you need to know about alcohol and nursing.

Less Is More

Breastfeeding or not, people should not drink more than the amounts recommended by leading health organizations, said Conover. (For females, that's one drink per day, and for males, two.)

The CDC says that not drinking alcohol is the safest option while breastfeeding. However, moderate drinking (defined as up to one standard drink per day) is not known to be harmful to the infant, especially if you wait at least two hours after a single drink before nursing.

Timing Is Key

It's probably best not to breastfeed your baby as you're drinking or right after drinking. "If a mom is going to drink alcohol, she should wait at least three to four hours until breastfeeding the baby," said Dr. Herway. (The CDC says to wait a minimum of two hours.)

"The amount of alcohol in breast milk is very similar to the amount in the woman's blood and alcohol is a fast-acting drug," explained Conover. "It peaks pretty fast after you drink...It moves in and out of milk."

Alcohol could take longer to peak in some people, so pay attention to how you feel in addition to how long it's been since you finished your drink. "If you're still feeling woozy, it's like the canary in the coal mine," said Conover. "The alcohol level is [still] too high in the bloodstream and in the breast milk."

Plan Ahead When Possible

If you know you're going to drink and your baby will need to eat not long after, make sure you have some stored breast milk or formula ready to go, said Conover. If you do bottle-feed your baby after having a drink, you can "pump and dump" to alleviate breast pain that may result from skipping a feeding.

"We get a lot of calls [from mothers] on St. Patrick's Day and New Year's Eve," said Conover. "They're calling because they'd like to still have a life and they want to take good care of their babies. They're responsible."

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