I am being told the opposite of this. Progesterone causes breast cancer. IMO when the balance is out of wack, then the protectiveness is tipped toward disease state.

"When estrogen dominates there is also a strong breast cancer risk, so it’s important to protect yourself, if you suspect you have low progesterone. I talk about the breast cancer and estrogen link more here in this post."

"It’s not surprising then, that research from the University of Adelaide in Australia has confirmed that progesterone may be beneficial in treating breast cancer."


https://hormonesbalance.com/article...lance-hormones/