There is simply no way of knowing whether having a vaccination during pregnancy can cause Autism -it is a very long bow to draw, and the research is just not there to back it up - especially since Autism is often not diagnosed until the child is older than 2 years of age - so there could be any number of reasons why children are autistic, and it cannot be linked to one single causative factor, especially things that you may or may not have done during pregnancy.