i don't know if it's the cold that is making them hurt, but you could try putting some Lanolin on them before you swim. I like the one in the purple box, I think it is called Lanoish for breastfeeding mothers and is supported by La Leche Leauge. You can find it at Meijer in the baby section, I think it is near the bottles and stuff. My nipples were so sore around 25 weeks, that I couldn't even stand to wear anything on top. A freind suggested using the Lanolin twice a day and before showering, and it has been a lifesaver. Now, I just use it in the morning. I hope this helps, and that you start feeling better!

oh, i def know how you feel with this one. everyone was telling me my boobs were going to hurt when i got pregnant but they didnt say it was going to be happening already, they always said it'd happen after pregnancy or at the very end. but my boobs, mainly just my nipples, ALWAYS hurt when i get cold.. they hurt so bad i just have to rub them until eventually the pain goes down.. sometimes it is so bad i feel like i could cry. apparently its normal though, so i just try and get through it.

it is probably them getting hard when you are cold.
is there no heated pool you can use?
MINE KILLED until the last trimester (shoooting pains that nothing stopped).
Whatever you do, DO NOT rub or stimulate your nipples. It is bad for you because it can cause milk to come or contractions.
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