hi Emma,
Sorry I havent got back to you sooner.
A normal pulse rate is anywhere between 60 & 100 beats per minute. When you are pregnant this can increase slightly because of the larger volume of blood you have on board. This too can also cause what feels like palpititions.
In terms of PE, there is some anecdotal evidence that palpitations can be a warning sign but I found nothing to consolidate this.
Most probable causes are anaemia or stress. Of course you can have palpitations & it be nothing to do with pregnancy or PE.
As always though, if you are worried get it checked out. Your GP can easily organise a 24 hour ECG or scan to make sure everything is tickety boo!
Good Luck
Liz