@Ladyfat I'm intrigued by people saying the rise in autism is due to better antenatal/neonatal care meaning more babies with these conditions survive. But we're not talking about conditions that would kill a newborn! We're talking about the huge rise in what used to be called Aspergers, or high-functioning autism, where people can live perfectly okay lives with these conditions.
There may be a small rise in kids whose autism is comorbid with genetic disorders which cause global developmental delay who might fall into the "better neonatal care" category, but the huge rise is not in these children.