Ebbie,
My gut tells me that autism is related to something in our every day environment. Artificial flavors or dyes, cleansers. Wax on vegetables. Something we take for granted that at the wrong time in a pregnancy produces anomalies. My 2 cents.
I remember children in my childhood with Down Syndrome and Cerebral Palsy but not autism or even Asberger's.
No babies suddenly disappeared from view when they proved to be "damaged". This is a recent epidemic and when the cause(s) is discovered, we will be horrified. At the same time, given the existence of evidence of genius for math and music among autistic adults and children, there may be something positive to come out of it. A new look into how and why the brain develops.
SINS, musing.