• Various studies suggest that the ratio of autistic males to females ranges from 2:1 to 16:1. The most-up-to-date estimate is 3:1.
  • In Leo Kanner's 1943 study of a small group of autistic children, there were four times as many boys as girls.
  • Lorna Wing (renowned psychiatrist and co-founder of our charity's first diagnosis centre)  found in her 1981 paper on autism and sex ratios in early childhood, that among people with a diagnosis of 'high-functioning autism' or Asperger syndrome (as it was called at the time) there were 15 times more men and boys than women and girls, while in autistic people with learning difficulties, the ratio of men and boys to women and girls was closer to 2:1.
  • In a much larger 1993 study of Asperger syndrome in mainstream schools in Sweden, Ehlers and Gillberg found a boy to girl ratio of 4:1.
  • Brugha's 2009 survey of adults living in households throughout England found that 1.8% of men and boys surveyed had a diagnosis of autism, compared to 0.2% of women and girls.
  • In 2015, the ratio of men to women supported by the National Autistic Society’s adult services was approximately 3:1, and the ratio of boys to girls in our charity’s schools was approximately 5:1.
  • In a 2017 study, Loomes and other researchers analysed existing prevalence studies and found that the male-to-female ratio was nearer 3:1.

Many of the autistic women we’ve spoken to have talked about getting a late diagnosis, or have had difficulty getting the support they need.

As part of our Stories from the Spectrum series, we interviewed several women and girls, who shared their experiences with us.

"I feel autistic women are more likely to be described as ‘anxious’ and an autism diagnosis overlooked, since it can challenge gender stereotypes."
Dr Camilla Pang

Why are more men diagnosed as autistic?

There have been various theories to explain why more men and boys get an autism diagnosis.

Please note:

Research and knowledge about autism changes constantly. Some of these theories may not reflect how we think about autism today.


Further reading

Girls and Autism: Flying Under the Radar - useful advice for parents and teachers on supporting autistic girls in school

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