Currently more males are diagnosed as autistic than females and this appears to be a worldwide phenomenon. Compared to males, females are at a much higher risk of their autism going undiagnosed with difficulties commonly misidentified or missed entirely. Anecdotal information from late diagnosed autistic women suggests that this issue is likely to have a significant impact on their mental health, emotional well-being, employment opportunities, personal relationships and vulnerability as a result of their needs being unrecognised and going unmet for many years. A common experience seems to be that many women only realise or have it confirmed they may be autistic when their child is diagnosed with autism. All the evidence points towards autism being diagnosed early for the most positive outcomes for individuals and females are no exception.

Diagnosis rates

  • Throughout the history of autism as an identified condition various studies, alongside personal accounts and evidence have come up with male to female ratios ranging from 2:1 to 16:1
  • An early pioneer in the autism field, Kanner studied a small group of autistic children and found there were four times as many boys as girl (1943).
  • Another early pioneer (1944), Asperger believed no females were autistic though he later revised this thinking.
  • More recently (1981) Wing found that of those considered ‘high-functioning autistic’ or Asperger Syndrome (autistic people with an average to above average IQ) the ratio was 15 males to every 1 female. For autistic people with learning difficulties the ratio was around 2 males for every female.
  • In a study of Asperger Syndrome in mainstream schools in Sweden in 1993, Ehlers and Gillberg summarised the ratio was 4 males to every female.
  • In 2009 in a survey of adults living in households throughout England by Brugha it was found that 1.8% of males surveyed had a diagnosis of autism, compared to 0.2% of females.
  • More recently (2015) in a study done by the National Autistic Society (UK) the ratio of men to women supported in their adult services was approximately 3:1, and the ratio of boys to girls in their schools was 5:1.

Why might there be such a distinct gender split?

There is currently no one theory that explains the reasons, it is likely to be as a result of the interplay of several phenomena:

  • The female autism profile does not always fit with the profile associated with males (Bargiela, Steward and Mandy, 2016) on which most of the assessment tools are based, due to historical gender bias as implied in the previous section. As a result, many females are going un-diagnosed or misdiagnosed with mental health difficulties such as social anxiety , selective mutism, bi-polar disorder, depression, alcoholism/drug abuse, school refusal, eating disorders and other emotion or hormone related challenges (“diagnostic overshadowing”).
  • The impact of the Extreme Male Brain theory ( Baron-Cohen , 2002) that autism is an “extreme version of maleness” ( systemising v empathising) compounding the commonly held myth that females cannot be autistic because they are the empathisers in the human population and males are the systemisers, as it is claimed are many autistic people.This is also related to the myth that autistic people cannot empathise and are insensitive to others . For some autistic people and females in particular it may be entirely the opposite and they are hyper vigilant of others and care deeply but may misread the subtleties of social communication signals which then makes them vulnerable to high levels of abuse and bullying /hate crime.
  • Genetic differences mean that girls are less likely to inherit autism (Skuse,2000).
  • The male population tend to be more likely to have difficulties or be “damaged” (Rimland, 1964), either inherited, through infection or other conditions so therefore males are more likely to be autistic.This theory does however make the assumption that autism is a form of damage as opposed to a human phenotype which is part of the neurodiversity of the human race.
  • Females who do not have early or more profound developmental delays learn to “mask” or “camouflage”( Dean, Harwood and Kasari ,2017) their social, communication and sensory issues to try to fit in and be like others( “passing”) . This can take a huge toll on their physical and mental health.
  • Autism characteristics in girls and young women are less recognised or reported by teachers (Egerton and Carpenter, 2016) and school is often a place where autistic children are first identified.

For more detailed information about the issues that females on the spectrum experience and the impact of lack of knowledge and awareness of this public health and education issue please attend one of my day or half day courses on autism in females ( see for courses running this year) or you can commission me to deliver a course by contacting me via the Contact Page on this website.


The Experiences of late-diagnosed women with autism spectrum conditions: An investigation of the autism phenotype – Bargiela, Steward and Mandy, 2016

The extreme male brain theory of autism Baron -Cohen, 2002

Missed diagnosis or misdiagnosis: girls and women on the autism spectrum -Gould and Ashton-Smith, 2011

Sex ratios in early childhood autism and related conditions -Wing, 1981

Imprinting, the X-chromosome, and the male brain: explaining sex differences in the liability to autism – Skuse, 2000

The art of camouflage: gender differences in the social behaviours of girls and boys with autism spectrum disorder-Dean, Harwood and Kasari ,2017

Girls and Autism: Flying Under the Radar-Egerton and Carpenter,2016

National Autistic Society, 2018

Women and Girls with Autism Spectrum Disorder -Hendrickx, 2015

Spectrum Women. Walking to the Beat of Autism-Editors Cook and Garnett, 2018