Does progesterone taken by men act only as a contraceptive?

Hi Catherine,

Greetings from Vancouver, B.C.

I read that the “… side effects for Natural Progesterone taken in physiologic doses are minimal. In a study in the Medical Tribune fifteen years ago, progesterone was given to college age men which resulted in no change to general stamina, vigor or sex drive. However, sperm maturation was inhibited.”

In other words, this study showed that it appears that progesterone taken by men in physiologic doses may act only as a contraceptive.”

Have you heard anything about this?

All the best,

Michael

G’day Michael!

Yes, I have read this comment before. In fact, the information you refer to was taken from Dr John Lee’s earlier publication ‘What Your Doctor May Not Tell You About Menopause’, first published in 1996. Dr Lee goes on to state that “since many testosterone receptors also accept progesterone (and with similar results), it is likely that a biofeedback mechanism in the brain reduces testosterone production when high levels of progesterone are present. Thus it appears that pharmacologic doses of progesterone in men act only as a contraceptive.”

The more recent article Male Contraceptives plus HRT for men explains this theory in pretty thorough detail.

Please note the words ‘progesterone’ and ‘progestin’ referred to throughout this interview with the good Professor David Handelsman are actually the same synthetic progestins found in conventional HRT. More recently the Women’s Health Initiative study was stopped short one year ago when it became clear that estrogen-progestin increased the risk of breast cancer, heart attack, and strokes.