The avid readers on holistic topics among you will know that there have been repeated claims about mercury being the cause of the unprecedented increase in autism that was seen in the last 20 years. That may be true or not, for what I know it has not been very well established scientifically. Now regardless of that, I would never let myself or my child be injected with any mercury for enough other reasons.
A connection to autism which apparently has been sufficiently established is that with certain antidepressants, namely SSRIs. If those are taken during pregnancy, the chance of the child to later suffer from autism doubles, if taken in the early stages of pregnancy, it is even four fold! Same thing here… it is not like we did not already have enough reasons not to take those drugs. But in any case, this is yet another one.
See the report on CNN: http://edition.cnn.com/2011/HEALTH/07/04/antidepressant.pregnancy.autism.risk/index.html.