In short, we are not exactly sure. It is more difficult to come up with a precise figure for the prevalence of FASD than it is for many other disorders because FASD is so rarely diagnosed. If you were able to access official records of FASD diagnosis, as some researchers have, you would think it was a very rare disorder indeed. But rates of diagnosis are so low because there is so little infrastructure dedicated to FASD. There is a lack of training for professionals and a lack of public understanding, so children with FASD typically either miss out on services altogether or are given other diagnoses and support which may be inappropriate to their needs.
We know this because of a research method called active case ascertainment (ACA). In an ACA study, instead of relying on official records, researchers actually go out into the community and look for cases of a disorder using diagnostic methods. ACA methods have been employed for the assessment of FASD prevalence in the United States, Canada, Italy, Croatia, Poland, and South Africa, where they typically generate FASD population prevalence estimates of around 2-4%. This is many times greater than official figures would suggest, which is how we know most children with FASD are still out there, unrecognised, undiagnosed, and unsupported.
Recently, the first ACA study of FASD prevalence in the UK was conducted by a team of researchers and clinicians led by the FASD research team at the University of Salford in Greater Manchester. This was a fairly small local study conducted in three mainstream primary schools. Our researchers conducted physical and psychological assessments on a sample of children aged 8-9, took family histories, and analysed saliva samples to rule out any genetic causes of developmental impairment.
From the sample of 220 children, four children were found to have FASD and a further four children had evidence pointing to FASD without reaching criteria for diagnosis. Based on this, the study generated an estimated FASD prevalence rate of between 1.8% and 3.6%. This is in keeping with ACA studies conducted abroad, as well as previous modelled estimates for the UK. None of these children had been previously identified as having a neurodevelopmental disorder, and we were also able to identify a further 16 children who had different disorders such as autism and learning disabilities, who had not been identified.
This is the first time that FASD prevalence has been directly assessed in the UK and is the clearest indication yet that FASD is a big problem here. But figuring out the scale of FASD is only a first step. Now that we have better evidence of prevalence, we can be better prepared to tackle it. This will require more funding for FASD services across the country and research into effective programmes of support for families affected by FASD, which we are also working on at the University of Salford.
It has been estimated that Ireland has the highest level of alcohol consumption in pregnancy anywhere in the world. FASD research and infrastructure are only in their most early stages in Ireland, with no specialist clinics, services or research centres. The prevalence of FASD in Ireland is likely to be even higher than in the UK, and researchers from the UK and Ireland are starting to talk about the possibility of a prevalence study there. This could be a hugely important step towards support and services for people affected by FASD in Ireland.
