The guide

Alcohol and fertility, for women and men trying for a baby

By GyroscopeUpdated November 15, 20268 sources

If you’re trying for a baby, the simplest plan is to stop drinking now. The CDC says there’s no known safe amount of alcohol “during your pregnancy or when you are trying to get pregnant.” For men, sperm take about two months to make, so cutting back two to three months ahead gives every sperm a clean start.

Couples planning a baby get a lot of advice aimed at the woman and very little at the man. Alcohol is a good example. The pregnancy rule is clear and well known. What’s less known is that drinking can lower the odds of conceiving for both partners, and that men’s timeline starts earlier than most people think.

For women: the odds each month

The chance of conceiving in a given month is called fecundability. A 2017 review of 19 studies and 98,657 women found it was 11% lower in light drinkers (up to 12.5 g a day, a bit under one US drink) and 23% lower in moderate to heavy drinkers, compared with women who didn’t drink. Each extra 12.5 g a day lowered it about 2% more.

Not every study finds an effect at low amounts. A Danish study of 6,120 women trying to conceive found no clear difference below 14 drinks a week, though women at 14 or more had 18% lower odds, and the result wasn’t certain. The authors noted they couldn’t tell whether women drank heavily during their fertile days, which might matter more than the weekly total.

The bigger reason to stop is the first weeks of a pregnancy you don’t know about yet. The CDC says all types of alcohol can be harmful, including red or white wine, beer and liquor, and that there’s no known safe amount.

For men: sperm take two months

Sperm aren’t made overnight. In a 2006 study, 11 men drank water labeled with a harmless tracer for three weeks, and the labeled sperm showed up in their semen an average of 64 days later, between 42 and 76 days. So the sperm you’ll use next month started forming about two months ago, and whatever you drank then is part of their story.

Drinking does change semen. A 2014 study of 1,221 young Danish men found lower sperm counts and fewer normally shaped sperm with more alcohol, starting at more than 5 drinks a week (Danish drinks of 12 g) and strongest above 25. Men who drank more than 40 a week had 33% lower sperm concentration than men who had 1 to 5. A 2017 review of 15 studies and 16,395 men found that daily drinkers had less semen and fewer normal sperm than occasional drinkers, while occasional drinking didn’t show much effect.

Those are studies of sperm, not babies, and nobody has tested exactly how many weeks of not drinking is enough. But with sperm taking about two months to make, cutting back two to three months ahead covers a full cycle.

How far ahead to stop

After the baby: breastfeeding

The CDC says not drinking is the safest option while breastfeeding, and that up to one standard drink a day isn’t known to harm the baby. Alcohol from one drink can be found in breast milk for about 2 to 3 hours, and from two drinks for about 4 to 5. If you have a drink, wait about 2 hours per drink before nursing. Pumping and throwing the milk away doesn’t clear alcohol any faster, but you can feed milk you pumped before you drank.

If it’s hard to stop

If you’re pregnant or trying and finding it hard to stop, tell your doctor or midwife. Treatment works, and they want to help. If you can’t stop has free, confidential help, including SAMHSA’s helpline at 1-800-662-4357. The 2025-2030 US Dietary Guidelines list pregnant women among the people who should avoid alcohol completely.