I have Autism Spectrum Disorder/Asperger's, and I believe that there isn't so much a rise in autism as there is an increase in people who are identified as Autistic due to more awareness and knowledge on the part of doctors. Back in the '60's, when I was young, only the ones with severe Kanner's Syndrome Autism were diagnosed as Autistic, and very few people really acknowledged anything that affected people to a lesser degree. You might be diagnosed with co-morbid learning disorders, such as dyslexia or dyscalculia, or might be misdiagnosed as being "hyperactive" or "hyperkinetic" if you fell in the high functioning or Asperger's range of Autism. Even in the 80's the focus was on ADHD, and it wasn't until the 90's that I even heard of Asperger's.

interesting read here:
[iflscience.com]

article conclusion: So, while it appears that autism is rapidly on the rise, it’s actually more likely just the result of medical improvements helping doctors diagnose more cases, in turn allowing more and more people with ASD to access the help they need.

I believe it is the pesticides, hormones, and food preservatives in our food. We are being poisoned by Monsanto and the other big Chemical Companies.

not vaccinations then....putting on my flack jacket LOL

I'd suspect it's simply more accurate identification of it.

I took a University course in Microbiology, the Human Gut Microbiome, about the microbes that live in the gut. We have co evolved with them. Changes in the way we live, with hygiene, living indoors, and the use of antibiotics have changed our gut microbiomes substantially. They also change as we age. They have sequenced gut microbe populations from humans in many areas including ones that still live a fairly wild existence, like nomadic African tribes. There is evidence that the development of our immune system is affected by our gut microbes. Some postulate that as a reason for increased prevalence of autoimmune disorders. A connection between the onset of Celiac disease and the use of antibiotics has been shown. Some scientists are working on a possible connection between gut microbes and autism. That course was a few years ago and I don't know where the research has gone. That is a possible reason for increased prevalence.

I’ve an unprofessional suspicion, though having worked amid students with. Folks putting children off longer, and longer … thus a loss of viability and increase in defects in both eggs and sperm.. I believe the same has been determined with Downs Syndrome, but since that can be determined prior to birth, aborted.