I don't think anyone has the knowledge to answer you. It is all speculation on the part of most. There is some authoritative info by W_Llewellyn that prog-gyno is a myth because it still needs estrogen to develop gyno. I read in a medical journal that the progesterone-receptor in an "estrogen induced protein" which would lend support to the theory that w/o estrogen's influence, you wont get gyno from progesterone. I just wish someone would do a poll: "Who has NO problems with gyno when on Nolvadex AND Testosterone but has problems with gyno on Nolvadex AND Deca/Fina?" In other words, has anyone gotten "progesterone gyno" while taking an anti-estrogen -- namely, Nolvadex? If the answer is yes, then there is prog-gyno that develops independently of estrogen's influence. The only problem is that all kinds of people will chime in when the only people who can speak authoriatively are the ones who can answer, FROM EXPERIENCE, "Who has NO problems with gyno when on Nolvadex AND Testosterone but has problems with gyno on Nolvadex AND Deca/Fina?"