Pregnancy information

Alcohol and illegal drugs

This page covers:

Drinking alcohol while pregnant

It's recommended that if you're pregnant or planning to become pregnant you should not drink alcohol. This will keep any risk to your baby to a minimum.

Drinking in pregnancy can lead to long-term harm to the baby, with the more you drink, the greater the risk.

Is it safe to drink alcohol when pregnant?

The Chief Medical Officers for the UK recommend that if you're pregnant or planning to become pregnant, the safest approach is not to drink alcohol at all to keep risks to your baby to a minimum.

Drinking in pregnancy can lead to long-term harm to the baby, with the more you drink, the greater the risk.

How does alcohol affect my unborn baby?

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 and doesn't mature until the later stages of pregnancy.

Your baby cannot process alcohol as well as you can, and too much exposure to alcohol can seriously affect their development.

Drinking alcohol, especially in the first three months of pregnancy, increases the risk of miscarriage, premature birth and your baby having a low birth weight.

Drinking after the first three months if your pregnancy could affect your baby after they're born.

The risks are greater the more you drink. The effects include learning difficulties and behavioural problems.

Drinking heavily throughout pregnancy can cause your baby to develop a serious condition called foetal alcohol syndrome (FAS).

Children with FAS have:

  • poor growth
  • facial abnormalities
  • learning and behavioural difficulties

Drinking less heavily, and even drinking heavily on single occassions, may be associated with lesser forms of FAS. The risk is likely to be greater the more you drink.

How to avoid alcohol in pregnancy

It may not be as difficult as you think to avoid alcohol completely for nine months, as many women go off the taste of alcohol early in pregnancy.

Most women do give up alcohol once they know they're pregnant or when they're planning to become pregnant.

Women who find out they're pregnant after already having drunk in early pregnancy should avoid further drinking.

However, they should not worry unnecessarily, as the risks of their baby being affected are likely to be low.

If you're concerned, talk to your midwife or doctor.

What is a unit?

If you do decide to drink when you're pregnant, it's important to know how many units you are consuming.

One UK unit is 10 millilitres (ml) - 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

If you have an Android smartphone, iPhone, iPad or iPod touch, you can download the free One You Drinks Tracker from Google Play or the iTunes App Store. It allows you to keep a drinks diary and get feedback on your drinking.

Alcohol support services

If you have difficulty cutting down on what you drink, talk to your midwife, doctor or pharmacist.

Confidential help and support is available from local counselling services:

  • DAN 24/7 is the All Wales Drug and Alcohol Helpline which you can contact on 0808 1410044. Dan 24/7 is a free and confidential drugs helpline.
  • Drinkline is the national alcohol helpline. If you're worried about your own or someone else's drinking, call this free helpline on 0300 123 1110 (weekdays 9am to 8pm, weekends 11am to 4pm)
  • Find your nearest alcohol support services.

Illegal drugs in pregnancy

Using illegal or street drugs during pregnancy (including cannabis, ecstasy, cocaine and heroin) can have a potentially serious effect on your baby.

If you regularly use drugs, it's important to tackle this now you're pregnant. It's best not to stop abruptly without first seeking medical advice as there may be withdrawal problems or other side effects.  

Getting help

If you use drugs, it's important to seek help straight away so you can get the right advice and support.

You can get help from: 

  • your maternity team
  • your GP
  • specialist treatment services

They won't judge you and can help you access a wide range of other services, such as antenatal and family support. 

You can also contact FRANK for friendly, confidential drugs advice, including information on the different types of help available. The FRANK helpline is open 24 hours a day on 0300 123 6600.

What if I took drugs before I knew I was pregnant?

If you took a drug without realising you were pregnant on a one-off occasion, try not to worry - it's very unlikely to have affected your baby.

However, if illegal drugs are part of your life, getting help can really improve the outlook for you and your baby.


Last Updated: 10/05/2023 13:15:34
The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website nhs.uk