If (you're pregnant and) you get a fever you should consult with your dr. before reaching for any meds. since it's always a good idea to know the underlying cause of the fever.
I probably know of at least a dozen people who had some type of cold/fever during their pregnancy, including me, both times and I never took anything. I think a lot depends on how high one's temp gets and if it's high enough or going on long enough to take tylenol then my guess is, pg or not, one should always seek medical help first.
Just my 10 pence and also, neither of my boys have been diagnosed with any kind of developmental problems and I had quite a few fevers the second time around since my first was in daycare and always coming home sick and passing on to me, whatever ailed him.