How a mum-to-be’s drinking can have serious consequences on her baby’s growth and development.

The more you drink when you're pregnant, the greater the risk you are taking with your baby’s health. Miscarriage, stillbirth, premature birth and small birth weight are all associated with a mother’s drinking during pregnancy. Foetal exposure to alcohol is also the leading known preventable cause of intellectual disability (1). All of these potential risks are why the government advises pregnant women and those trying to conceive to avoid alcohol altogether. 

View our
Alcohol and pregnancy facts page for the full details of the government’s advice.

 One condition you may not have heard of is called Foetal Alcohol Syndrome (FAS) and it affects the way a baby’s brain develops. First discovered by two doctors in the US in 1973, how serious the condition is depends on how much alcohol a mother drank during pregnancy. The World Health Organisation quotes a 2005 US study which estimated that one in every 1,000 children are born with FAS (2).

What is foetal alcohol syndrome?

Children with FAS have problems with their neurological development, abnormal growth, and have characteristic facial features which result from their foetal exposure to alcohol (3).

Neurological problems are caused by damage to the central nervous system (brain and spinal cord). The problems experienced are likely to change as an infant grows up and different problems may be seen at different stages of development, from childhood, adolescence, and into adulthood.

These may include: learning disabilities, poor academic achievement, poor organisation, lack of inhibition, difficulty writing or drawing, balance problems, attention and hyperactivity problems.

Children with FAS have problems with their neurological development, abnormal growth and have characteristic facial features which result from their feotal exposure to alcohol.

The characteristic facial features can include: small and narrow eyes, a small head, a smooth area between the nose and the lips and a thin upper lip.

Children with FAS can also occasionally have additional problems such as:

  • Hearing and ear problems

  • Mouth, teeth and facial problems

  • Weak immune system

  • Epilepsy

  • Liver damage

  • Kidney and heart defects

  • Height and weight issues

  •  Hormonal disorders

How FAS develops during pregnancy

When a pregnant woman drinks, the alcohol goes across the placenta to the foetus via the bloodstream,” says Dr Raja Mukherjee who works for Surrey and Borders Partnership NHS Foundation Trust. “The foetus’ liver isn’t fully formed, so it relies on the mother's liver to metabolise (break down) the alcohol. When the alcohol passes from the mother into the foetus' body it lacks oxygen and the nutrients needed for its brain and organs to grow properly. “White matter in the brain, which is responsible for speeding up the processing of information, is sensitive to alcohol,” says Dr Mukherjee. “So when a mother drinks, it affects the development of her baby’s white matter.”

Timing is another medical factor in the development of foetal alcohol syndrome. A baby’s facial features are formed during weeks six to nine of pregnancy. Professor Neil McIntosh, an Edinburgh-based neonatologist, says scientific evidence shows that mothers who drink during this three-week window are more likely to have babies with the facial deformities associated with FAS. Damage to the baby’s organs through drinking is most likely to happen in the first three months.

 However, a baby's brain and spinal cord, which control most functions of our body and mind, continue to develop throughout the nine months of pregnancy. This means that damage to these vital systems may happen at any point during the pregnancy.

Want the facts on alcohol and pregnancy?

Foetal Alcohol Spectrum Disorder (FASD)

Since foetal alcohol syndrome (FAS) was first described in the 1970's, it has become clear that there is a spectrum of abnormalities resulting from foetal alcohol exposure, not only FAS.

Foetal Alcohol Spectrum Disorder (FASD) is the umbrella term used to describe this spectrum of abnormalities, with FAS lying at the most severely affected end of the spectrum.

There are no accurate records of the incidence of FASD in Western countries, but experts estimate that it may be as high as one child in 100 is born with FASD (3)(4).

FASD Signs and Symptoms

It is more difficult for a specialist to diagnose FASD than it is FAS. This is because children with FASD may not have facial deformities. It might not be until they start going to school and interacting with others that one or more of the following symptoms – which also affect children with foetal alcohol syndrome – show up:

  • Learning difficulties

  • Problems with language

  • Lack of appropriate social boundaries (such as over friendliness with strangers)

  • Poor short term memory

  • Inability to grasp instructions

  • Failure to learn from the consequences of their actions

  • Egocentricity

  • Mixing reality and fiction

  • Difficulty with group social interaction

  • Poor problem solving and planning

  • Hyperactivity and poor attention

  •  Poor coordination.

Treatment for children

GPs can refer children with FAS and FASD to community paediatricians who are likely to investigate problems further with psychologists, psychiatrists, speech and language therapists and specialists for organ defects.

Dr Mukherjee runs a clinic for children and adults over six with FAS and FASD. He diagnoses FASD by excluding similar conditions such as Attention Deficit Hyperactivity Disorder (ADHD). “Then it’s about working with the child, parents and other professionals, such as teachers, to find a management strategy for the condition,” he says. “For example, parents can learn to repeat instructions for children and use simple language and teachers should allow them more time and provide extra supervision.”

Early diagnosis is key. Research shows that people who have FAS or FASD go on to experience “secondary disabilities” – those not present at birth – which could be prevented with appropriate support. These include mental health and alcohol and drug problems. “Early diagnosis allows the stability and management that children with FAS or FASD need to be invoked earlier,” says Professor McIntosh.

Advice for mums-to-be

We don’t know how much alcohol is safe to drink in pregnancy. It depends on various factors such as how fast a mum-to-be absorbs alcohol, her physical health, diet and what medication she is on. It’s why the government advises pregnant women and those trying to conceive to avoid alcohol altogether.

If you didn’t know you were pregnant and you have been drinking above the government’s lower risk guidelines, don’t panic. Talk to your GP or midwife about any concerns you may have. Just because you may have drunk does not mean you have necessarily done damage.

 “If you drink a low amount when you are pregnant your baby has a low risk of developing FAS or FASD,” says Dr Mukherjee. “If you drink heavily you have a high risk. If you don’t drink, there’s no risk at all.”

Want more advice on drinking while pregnant?

Alcohol and conception

If you are trying to conceive, you should aim to reduce your alcohol consumption to a minimum, and ideally stop drinking altogether. If you are a regular drinker, try cutting down on alcohol gradually. Start off by reducing your drinking each day, and then try having a few alcohol free days a week before aiming to have only an occasional drink or preferably stop drinking altogether. Ask your partner to help you by cutting down drinking as well. If you are trying to conceive this is vital, as drinking impairs sperm count and heavy drinking can cause temporary impotence (5).

Back Back to top