text: sore boobs?? my boobs have been sore for the past 4 days, extremely sore.  it is not due to pms symptoms either.  i noticed sometimes when i sleep on my stomach it causes my boobs to ache for a couple days, does that happen to anyone else?  is there anything else that could cause them to be sore?  thanks! you cold be pregnant.. or maybe too much caffeine!! does it to me every time. if you are not pregnant, watch your caffeine intake.maybe it could be hormones too, or possibly this could be your body's response when you are ovulating..