There’s strong scientific evidence that alcohol can reduce fertility in both men and women. So why does alcohol cut your chances of having a baby? And how much is too much to drink when you’re trying to conceive?

Official guidance

The government alcohol unit guidelines does not have specific advice on the effects of alcohol on fertility.  But they do have specific guidelines for those trying to conceive.  It’s recommended that women trying to have a baby or pregnant women, should not drink alcohol at all to keep health risks to the baby as low as possible.

Recent reviews have shown that the risks of low birth weight, preterm birth, and being small for gestational age all may increase in mothers drinking above one to two units a day during pregnancy. Women who wanted to reduce that risk need to be particularly careful not to drink more than they intended to. Mothers with post-natal depression or those who lack support can be more likely to underestimate how much they’ve drank. The safest option is not to drink alcohol at all during pregnancy.

If you are already pregnant and drank only small amounts of alcohol in the early stages of pregnancy, the risk of harm to your baby is low. However if you are worried, you should talk to your GP or midwife. 

Drinking alcohol during pregnancy can lead to long-term health problems for the baby like Foetal Alcohol Syndrome (FAS). This is why the UK Chief Medical Officers' (CMO) alcohol unit guideline advice to pregnant women is that the safest approach is to not drink alcohol at all during pregnancy.

Female fertility and alcohol

However, alcohol doesn’t cause problems only after you’re pregnant. It can make women less fertile too. “There is a link between drinking and fertility, although exactly how alcohol makes women less fertile isn’t understood clearly,” says Dr Anthony Rutherford, a consultant in reproductive medicine and Chair of the British Fertility Society. “Many studies have shown that even drinking lightly can have an effect.” These include a study that showed drinking between one and five drinks a week can reduce a women’s chances of conceiving, and 10 drinks or more decreases the likelihood of conception even further1.

Does alcohol affect a healthy pregnancy?

Men, alcohol and conception

It isn’t just female fertility that’s affected by alcohol. Dr Patrick O’Brien, spokesperson for the Royal College of Obstetricians and Gynaecologists, says: “Excessive alcohol lowers testosterone levels and sperm quality and quantity in men. It can also reduce libido, and cause impotence."

If a man drinks heavily it can really reduce a couple’s chances of conceiving. However, if you reduce what you drink, these effects can be quickly reversed. (2)

Healthy lifestyle

A healthy lifestyle in general is key to making sure your fertility is in tip top shape. This includes eating well and exercising to make sure you’re a healthy weight. And of course, drinking within the government's lower risk guidelines – or stopping altogether – is part of this.

References 

(1) K Anderson, V Nisenblat & R Norman 2010; ‘Lifestyle factors in people seeking infertility treatment – A review’. Australian and New Zealand Journal of Obstetrics and Gynaecology, Vol.50, Issue 1, pp8--202
(2) M.A. Emanuele & NV Emanuele. ‘Alcohol’s Effects on Male Reproduction.’ Alcohol Health Research World 1998; vol.22, No.3,pp195-2011.