Hello A.,
I work daily with students with severe autism and write children's books on autism...so I hear a lot of talk on both sides of the conversation through my research for my books and just talk among parents. Suffice it to say, after all that I have read and heard, I am still not convinced one way or another. Autism is a neurological disorder with a genetic predisposition and some sort of environmental trigger sets it off. What that trigger is and how it affects different kids is unknown at this time. There are parents who have seen autism indicators prior to the shots and there are kids (obviously) who have received the shots with no problems. The importance of the shots is also relavent.
However, I would suggest looking onto more specific discussion sites related to autism to get a more in depth answer to your question from moms who are in the situation. http://www.autismspeaks.org/ (autism speaks) or www.autism-society.org (Autism Society of America) or look up some discussion boards relating to the topic. I must warn you that you will see fierce debate on both sides of this subject. I kind of stay neutral because my goal currently is to increase autism awareness to provide a more welcoming community to our brothers and sisters who are already diagnosed.
I know I haven't answered your question directly, but hope to have shed some light on where you might find more answers...or more questions.
Yes, currently autism is diagnosed 80% male, however, further research is finding that girls are undiagnosed due to gender issues related to diagnosis. So there likely are more than 1 out of 150 diagnosed in the future. The MMR debate just sparked again last week as ELI STONE premiered on ABC which highlighted a caes between a mother and a pharmaceutical company regarding autism/shots. Fictional of course, but sparked debate nonetheless.
Good luck in your hunt for answers,
J. Keating-Velasco
www.AisForAutism.net