It’s been nine or more arid months. You’re longing to pop the cork – in honour of New Year’s, of course – and the good news is: You can. No, you won’t be able to drown the craziness of the first few months in a haze of tequila, but you can, responsibly, have a glass of sauvignon blanc once in a while.

First, your crib sheet to drinking while breastfeeding

• Drinking alcohol while breastfeeding is fine, as long as it is occasional and minimal.
• It’s pointless to pump and dump breast milk. Your supply of fresh milk will simply refill with whatever your current blood alcohol level is.
• If you simply wait to sober up (a couple of hours after one to two drinks), your body will break down the alcohol and your breast milk will be alcohol-free.
• Even if you breastfeed while tipsy (not drunk), the amount that will reach your baby is minute.
• As a 2013 review of research concluded: “Occasional drinking while breastfeeding has not been convincingly shown to adversely affect nursing infants.”

Now, let’s break it down a little more.

Drinking while breastfeeding isn’t like drinking while pregnant.

When you’re pregnant, you share a blood supply with your fetus; your blood alcohol level is its blood alcohol level, at any given moment. That’s not to say you shouldn’t have a drink, ever, during your pregnancy, but the alcohol reaches the fetus involuntarily and at peak amount.

When you breastfeed, you have control over if and in what amount that alcohol passes to your baby. Your breast milk will contain roughly the same alcohol content as your blood, but as your body metabolizes the alcohol in your blood stream, you sober up and the alcohol content of your breast milk diminishes, too.

This is why the concept of ‘pumping and dumping’ is a pointless exercise; if you throw out your breast milk immediately after drinking, it will just re-up with an alcohol content of whatever your current blood alcohol level is (and might actually be higher than it was before – breast milk alcohol levels peak 30 to 60 minutes after finishing your drink).

Even at your tipsiest, your baby is likely to ingest only a negligible amount of alcohol.

Melinda Wenner Moyer over at Slate breaks down drinking wine while breastfeeding:

“If a 150-pound nursing mom downs four alcoholic drinks—say, four 5-ounce glasses of table wine—and then breast-feeds her 13-pound baby 4 ounces of milk when she’s at her tipsiest, her baby will end up with a blood alcohol concentration of 0.0038 percent—the same blood alcohol concentration her mom would have after consuming a mere 1.5 ounces of Bud Light (one-eighth of a 12-ounce bottle).”

You may feel more tipsy than your actual blood alcohol level.

It’s hard to say if it’s the wine or the dizzying heights of your first taste of ‘spicy juice’ after a long hiatus, but you might feel more tipsy than your actual blood (and breast milk) alcohol level. Research suggests that blood alcohol level peaks at a lower point for lactating women than others, even though those women reported still feeling tipsy.

Your baby may not eat as much or may have a fussy night.

Drinking alcohol while breastfeeding – or more accurately, breastfeeding after drinking alcohol without waiting the few hours it takes to clear it from your blood and breast milk – can have an effect on your child. While there’s no evidence of long-term harm, there are two things to be aware of.

First, your baby might not eat as much. Alcohol will inhibit your breast milk supply; in one study, infants fed 20% less after mothers had consumed alcohol. Not to worry, though – normal breast milk supply resumes, and infants ate more later to make up for the lesser feed.

Second, there is evidence that drinking breast milk after their mother has been drinking can affect babies’ sleep patterns. Research suggests they sleep less and experience fewer REM cycles, though these changes are temporary.

But there’s no evidence of any long-term damage, cognitive or otherwise.

Studies that link mothers’ alcohol consumption to babies’ cognitive damage tend to focus on heavy and prolonged drinking. One study from the 80’s found babies of mothers who consumed only one alcoholic drink at day while breastfeeding didn’t score as well on motor skills tests as babies of mothers who abstained — but, again from Moyer’s article:

“When these same researchers conducted a follow-up study six months later, they were unable to replicate their findings. By 18 months, in other words, the babies of moms who drank while breast-feeding scored the same on motor tests as the babies of moms who abstained.”

Still, no doctor is ever going to condone drinking while breastfeeding.

Just like no doctor is going to advise anyone to add a gin and tonic or two to their diet, a doctor isn’t going to say, “It’s totally fine to drink alcohol while breastfeeding.” Despite all of those articles you’ve seen on the health benefits of a glass of wine a day, alcohol is a toxin and can’t be described as healthy.

But there’s a bigger reason, too. The distinction between what is okay and what is harmful to your baby hinges on the difference between occasional, light alcohol consumption, binge drinking (for women, four or more drinks within two hours) and chronic alcohol abuse. And doctors are going to assume you’re under-reporting when you describe your drinking while breastfeeding as occasional and light, because, well, patients lie to doctors all the time.

Doctors are also concerned by the obvious: Alcohol impairs coordination and good judgment, two pretty critical factors in caring for a baby. And parental alcohol consumption has been tied to increased SIDS risk particularly among families who co-sleep.

But that doesn’t mean an occasional drink or two isn’t OK.

As long as you aren’t lying to your doctor (or yourself) and stick to an occasional glass of your favourite cocktail, wine or beer, drinking alcohol while breastfeeding is no big deal.