4.1 Autism in females
Prevalence estimates for autism in males are consistently much higher than for autism in females, suggesting that four times as many males are diagnosed as females. This male/female disparity may even be as high as 10:1 if considering only males and females with high-functioning autism. There is much ongoing research into genetic and other biological factors which might make boys more susceptible to autism than girls. But there is also increasing evidence that autism diagnoses in girls are being missed.
Experts believe that autism characteristics in girls and women do not necessarily match the stereotype of obsessive interest in machines and other physical systems, coupled with obvious social withdrawal. Girls on the autism spectrum may have more ‘typically female’ interests, such as fashion or fiction, such that an unusually obsessive focus on the interest, or an unusual way of engaging with it, goes unnoticed by parents and peers, especially in intellectually able girls. Through an interest in other people’s behaviour, and/or a strong desire to conform, girls may strive hard to appear sociable, emulating the behaviour of their peers. This is well illustrated in this extract from Liane Holliday Willey’s autobiography:
My mother tells me I was very good at capturing the essence and persona of people. At times I literally copied someone’s looks and their actions. I was uncanny in my ability to copy accents, vocal inflections, facial expressions, hand movements, gaits and tiny gestures. It was as if I became the person I was emulating.
Girls may work hard to camouflage their autism, struggling for years with an underlying sense of isolation and difference. Even where parents express concerns to professionals, for instance because their daughter is extremely ‘faddish’ about food, autism may be dismissed because other areas of the child’s behaviour ‘don’t fit’. An increasing number of females are receiving diagnosis in adulthood, sometimes after treatment for an accompanying condition such as depression or anorexia. Experts are considering whether diagnostic tools need adjustment to be more ‘gender neutral’. Nonetheless, underdiagnosis alone is unlikely to explain all of the marked excess of males over females on the autism spectrum, suggesting that there is also increased biological risk in males.
See Lai et al. (2015) for a review of the evidence and ideas covered in this section.