Mine were REALLY sore in the 1st trimester...they settled down a bit after 12 weeks, but then started to grow again. I still get aches now (5 months), but it's not everyday.
I had to buy a new bra in the 1st trimester (just up a cup size, eg 10D to 10DD) and then in the 2nd trimester, went 12D, and am now also wearing 12DD. Fortunately, they seem to be sufficient...I've already spent >$200 on bras that I'll only wear for another 4 months!
I'd recommend getting a new bra ASAP to ease the pain.
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