When I first got menopausal or peri-menopausal, I started using progesterone cream. I got terrible breast tenderness then.

I read somewhere (can't remember where) that fresh juiced vegetables and fruit (but more veg) was an answer. I think that really made a difference to me. Certainly the swelling/pain had stopped within about 5 weeks and I've had no sign since, even though I'm not still juicing.