I think that I have had a couple. They are not really uncomfortable its just a sort of sensation of my tummy feeling tight for a little while that soon passes. I am not sure that they are BH but I can't really attribute them to anything else.
I've been able to feel them since quite early in my pregnancy and get them quite frequently. I think maybe about 18 weeks was when I started feeling them just as a tightening sensation in my tummy for a few seconds, and as my belly has gotten bigger they have gotten more noticable. Most of the time they just feel like a strong tightening in my belly and it goes rock hard, but not actually painful. I did have two nights in a row at 30-something weeks where they went on for hours and were actually quite painful and I wondered after a while if I might be in labour LOL, but that hasn't happened again since. Only the non-painful kind thank goodness!
I started having a few BH's early on around 28 weeks but then they died away until later... I found I had them after a huge day of working too hard, so if I put my feet up they went away.
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