Paolosgirl - There isn't any research that shows that paracetamol is 100% safe in pregnancy, but it is assumed to be as its been around for a while and noone has ever shown a dangerous effect of it in moderation.
You can NEVER prove a theory, you can only DISprove one. That was the first thing I was taught at Uni regarding research. You can put a good argument forward and show the probability of something, but can never prove it 100%.
Now that a 'theory' has been planted in the minds of every parent.... it can only be disproven.... but that will never be satisfactory.
For those looking for a study showing that MMR is 100% safe, it will never happen. As with any vaccination, medication, treatment, food etc etc.
Agree whole-heartedly that more research needs to be carried out into just what triggers autism.