HEAD: Professor Sheila C. Hollins FRCPsych

St George’s Hospital Medical School




Overview of FAS

by Raja Mukherjee


Foetal Alcohol Syndrome (FAS) is a neurodevelopmental disorder caused by the use of alcohol during pregnancy. It is associated with both a physical phenotype as well as a life long behavioural phenotype, which is both pervasive and debilitating for the majority of people suffering with the condition.


How common is it?


Reports suggest varying rates of prevalence of the disorder. The full disorder of foetal alcohol syndrome is thought to have a prevalence of around 1 in 3000. This compares to other conditions such as Downs Syndrome 1 in 666, Phenylketonuria 1 in 14000, Fragile X 1 in 1000. Unlike these conditions and more similar to the picture seen in autism there appears to be a spectrum of problems from the most severe presentation of the full condition to a milder but still significant impairment of behaviour. This Spectrum (Foetal Alcohol Spectrum Disorder FASD) is estimated to have a prevalence of around 1 in 300. Also unlike the other conditions mentioned which also have behavioural and physical phenotypes FAS is not a genetic condition and thus is eminently preventable.


Most of the research on the incidence of this condition has occurred in America with studies also being carried out in South Africa and Scandinavia. What these have shown is that the prevalence is broadly comparable and thus it would be expected that similar rates would be found in the UK. Work needs to occur in this country to try and clarify if this is the case. A potential problem that exists currently is that studies show that young females in this country are partaking more in binge drinking. If this occurs at a time of venerability during pregnancy (see below) it will potentially lead to an increase in prevalence.


Who is at risk of developing this?


Everyone who drinks during pregnancy is potentially at risk. Studies to date have shown that the most common group to have children with foetal alcohol syndrome are people who drink chronically during pregnancy. There is an increasing literature of evidence, however to suggest that binge drinking as well as low doses of alcohol can cause damage. This may not be to the extent that would cause the full disorder but it is speculated that the behavioural problems will present themselves in individuals who are exposed to levels of alcohol in pregnancy. Specific venerable periods also exist during pregnancy when the foetus is more or less at risk of developing some of the phenotypic features, however as the brain develops throughout pregnancy there is no safe period for consumption in pregnancy. Due to the ethical problems of studying this in humans no specific data as to the exact safe level exists thus this data is extrapolated from animal models. The only definitely safe level is no alcohol at all.




How is this diagnosed?


Anecdotal evidence would suggest that it is under recognised and labelled more as ADHD or Conduct Disorder in childhood. This potentially leads to a diagnosis in some of personality disorder in adulthood. Whilst this is an acceptable diagnosis it misses the specific cause of the problem. Diagnosis can be made in one of two ways. Firstly by definition of a series of symptoms leading to a syndromal diagnosis. The second is in terms of an aetiological cause. ADHD would be considered a diagnosis of the former category and FAS the second. AS such rather than being mutually exclusive they are very likely to exist concurrently as diagnoses in a multiaxial fashion. This is more recognised as an appropriate way of making diagnoses.


Studies are currently being conducted by myself and others looking into the nature as to how well recognised FAS is by multi professional groups.


Do people get better?


FAS is a pervasive disorder. This means that is will never be cured and will never go away. It affects the basic structure of the brain and the way that it processes information. This is similar to Autism and other pervasive developmental disorders. Having said this unlike autism, with which the behavioural phenotype has some crossover, a majority of people have an IQ in normal range. Only 25 - 30% of  people with FAS have an intellectual disability. A majority will however suffer with behaviour problems.


AS with other conditions however studies in Germany and Scandinavia have shown that consistency and family support can lead to a better outcome. Also education especially in social skills can be of benefit. Many will still find it difficult and need lifelong support but some will be able to live normal lives in the community.


Is this a condition that needs support and awareness


FAS is by far the largest preventable cause of intellectual disability that exists. It is an ongoing financial burden to healthcare providers and in some cases to the criminal justice system. Awareness of this condition currently is minimal and thus more work both with health promotion campaigns and support for those already suffering with this disorder are vital.



Please note I have not included scientific references in this overview but would be happy to do so if requested.


Raja Mukherjee

Specialist Registrar/ Honorary Lecturer

Department of Mental Health ( Learning Disability)

St George’s Hospital Medical School, Cranmer Terrace, Tooting

London, SW17 0RE