"We shouldn't assume autism or Asperger syndrome will look the same in both sexes.
"There may be many factors leading to these conditions either being underdiagnosed or misdiagnosed in females, or leading females to require a diagnosis less often."
Judith Gould, of the National Autistic Society, said: "We hear from many women who have been diagnosed later in life.
"The way autism is presented in women can be very complex and so can be missed.
"It might be that due to misconceptions and stereotypes, many girls and women with autism are never referred for diagnosis, and so are missing from statistics.
"This may mean that many women who are undiagnosed are not receiving support, which can have a profound effect on them and their families."
"Characteristics such as shyness and oversensitivity, common to people affected by autism, are sometimes deemed to be typically female traits.
"However if a boy were to display such characteristics, concerns may be raised."
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