Experts are still unsure exactly how much alcohol is safe for you to have while you're pregnant, so the safest approach is not to drink at all while you're expecting.
What's the official advice?
The Department of Health recommends that if you're pregnant you should avoid alcohol altogether. And if you do opt to have a drink, it recommends that you stick to one or two units of alcohol (equivalent to one small glass of wine) once or twice a week to minimise the risk to your baby.
The National Institute for Health and Care Excellence (NICE) is the independent organisation responsible for providing national guidance on promoting good health and preventing and treating ill health.
NICE advice on drinking in pregnancy is that women should abstain from alcohol completely during the first three months of pregnancy because of the risks of miscarriage. And for the rest of pregnancy to drink no more than one or two units of alcohol once or twice a week.
The Royal College of Obstetricians & Gynaecologists (RCOG) says the safest option for women is not to drink at all during pregnancy, but adds that small amounts of alcohol in pregnancy (not more than one to two units once or twice a week) have not been shown to be harmful.
How is drinking in pregnancy potentially harmful?
When you drink, alcohol passes from your blood through the placenta and to your baby. A baby's liver is one of the last organs to develop fully and doesn't mature until the latter stages of pregnancy. So, your baby cannot process alcohol as well as you can and too much exposure to alcohol can seriously affect their development.
If you drink at any time during your pregnancy, the alcohol can affect your baby.
Drinking alcohol is potentially most harmful for your baby in the first three months of pregnancy when it is linked to miscarriage and birth abnormalities.
More recent research found that drinking in early pregnancy also increases the risk of premature birth and low birthweight.
Drinking in the second half of your pregnancy can affect how your baby grows and develops. Drinking more than the recommended one or two units once or twice a week can also affect your baby after they're born. The effects include learning difficulties and behavioural problems.
Drinking heavily (more than six units a day) throughout pregnancy can cause your baby to develop a serious condition called foetal alcohol syndrome (FAS). Children with FAS have:
- restricted growth
- facial abnormalities
- learning and behavioural disorders
Binge drinking, which is defined as drinking more than 5 standard drinks or 7.5 units in a single session (a bottle of wine is around 9 units) or regularly drinking over the recommended level may be associated with lesser forms of FAS. The risk is likely to be greater the more you drink.
The healthiest option
Experts still aren’t sure about the precise amount of alcohol that is safe to drink in pregnancy, but they do know that drinking even moderate amounts can be harmful.
So, you might decide that the safest option for you is to avoid alcohol completely for nine months. It may not be as difficult as you think, as many women go off the taste of alcohol early in pregnancy.
If you do decide to drink when you’re pregnant – and remember the official NHS advice is to stick to one or two units once or twice a week – it's important that you know what a unit of alcohol actually is.
One UK unit is 10ml (or eight grams) of pure alcohol. This is equal to:
- half a pint of beer, lager or cider at 3.5% alcohol by volume (ABV: you can find this on the label)
- a single measure (25ml) of spirit, such as whisky, gin, rum or vodka, at 40% ABV
- half a standard (175ml) glass of wine at 11.5% ABV
You can find out how many units there are in different types and brands of drinks with the Drinkaware unit calculator.
If you have an iPhone or iPod touch you can download the free NHS Drinks Tracker from the iTunes App Store straight from your phone. It allows you to keep a drink diary and get feedback on your drinking.
Read more about alcohol units.
Getting help cutting down
If you have difficulty cutting down what you drink, talk to your midwife, doctor or pharmacist.
Confidential help and support is also available from local counselling services (look in the telephone directory, or contact Drinkline on 0300 123 1110).
Read more advice on cutting down on drinking.