Pitocin used to be standard treatment. As in EVERY baby born in a hospital for over a generation was birthed with pitocin. Since Autism didn't take over an entire generation, the correlation is highly unlikely.
People REALLY want to assign blame to things they are afraid of. Unfortunately, it's just not that simple.
Take the whole immunization thing. In the medical community we knew that was bunk years (over 10) ago. Most knew it was bunk the moment the studies came out and hit peer review, because the studies were done wrong. One of the studies actually included a school for autistic children in the sample group. If, instead, they had included a school for gifted kids the "result" would have been that "immunizations cause giftedness". Totally bunk study, because it was done incorrectly. BUT people latched onto it, because it's a "controllable & blameable" thing. Meaning that a parent could "save" their child from autism by not doing x... which also translates into another parent having done something wrong. It's a human thing. THEY slipped because they're clumsy, *I* slipped because I stepped on an icy patch. It's a defense mechanism, to assign blame, found across every culture. Also, because of the regression that naturally happens around age 2, right when kids were coming into the docs, it created a false "positive" for people to see as "proof". Now... 1000 other things ALSO happen at different ages. If the regression happened at age 5, K would get blamed. If it happened around age 1 babyfood would be blamed. There's ALWAYS something else going on milestone or culturely at *any* age that something happens. That's why correlation isn't cause. MOST babies are born in hospitals... does that mean that hospitals cause _________? (fill in anything scary). No. It doesn't. For it to be causal the *majority* of people (or a strong percentage... like the percentage rates for Downs amongst "older" women is easily trackable, the percentage changes *noticeably* across the board) would have to be affected, instead of the standard %.
Since the immunization thing was *finally* debunked in the general public, there will undoubtedly be 5-20 new "things" that people are latching onto trying to find a cause for.
But it doesn't work that way. Autism just isn't that simple.