A protective effect in females may help explain one of the biggest mysteries
of autism: Why boys are five times more likely to develop the developmental
brain disorder than girls.
An estimated 1 in 88 children in the United States has an "autism spectrum
disorder." The condition, which can range from mild to severe, is characterised
by impaired communication and social interaction. Prevalence of autism is
increasing in the United States, although it's not clear if that's largely
because there's more awareness of the disorder.
Boys more prone than girls
For more about autism see the US National Library of Medicine.