Um yeah, so that’s not how autism works and no amount of parenting perfection can “prevent autism from developing”
The label of Autism is a very wide paint brush covering everything from extreme congenital disorders through to mild Asperger's. To say we can prevent all Autism is wrong, I phrased it in a way that was misleading -- I'm sorry, I was lazy and didn't want to type it out.
My DIL is a psychiatrist. She and I have had this conversation, a few times now. I was on your side of it at first and she woke me to the fact that in many cases as a society we are doing this to our own children. The science is still young, Europe is leaps and bounds ahead of the US in this area. We know it's caused by a combo of chemical imbalances (suspects are heavy metals and chemicals in much of the popular foods) combined with social development that is causing most of the light weight problems we see. Parts of the UK has laws restricting items such as certain food colorings that are known to increase the likelihood of Autism in children.
Congenital autism is identifiable at very young age. Developmental Autism is caused by the environment we force upon our kids and it is believed that it could be prevented in many cases.
So sorry, this is getting way off topic.