I only heard of this last night whilst reading someone else's thread. I thought I was having 'normal' Braxton Hicks.
Since Friday, every evening I have been experiencing an almost permanent tightening sensation along with period type pains. I do remember having this during my last pregnancy but I was a bit further along. I went in and was monitored for half an hour or so, although the tightenings were showing up they weren't strong enough to be true contractions.
I'm 31 weeks today.
I guess what I'm looking for is womens' experiences with this and whether it caused any problems.