A Danish study has tracked 657,461 children over a decade and has found no correlation between autism and the vaccine for rubella, mumps and measles. A journal published in The Lancet more than twenty years ago was the catalyst for speculation when it comes to the MMR vaccine being linked to autism. People still believe in the link to autism even though the author has been discredited and the journal has been retracted. The study found that "MMR vaccination does not increase the risk for autism, does not trigger autism in susceptible children, and is not associated with clustering of autism cases after vaccination".
Here's a link to the story > A Large Study Provides More Evidence That MMR Vaccines Don't Cause Autism