You are here

Progesterone therapy


Progesterone is women's second important and essential hormone and a partner of estrogen. Wherever estradiol is acting in women's bodies (bone, brain, breasts, uterus, skin and everywhere), progesterone is also acting. Women have two reproductive hormonesestrogen and progesterone. Men only have one (testosterone).

Progesterone therapy means taking natural progesterone (oral micronized progesterone) that is bio-identical. If, for cost reasons, a progestin must be substituted, medroxyprogesterone is the closest in action to progesterone (and, like progesterone, also improves hot flushes and increases bone density). Progesterone must be given at bedtime since its major "side effect" (smile) is to improve sleep; it is effective in a dose of 300 mg at bedtime daily which keeps the serum progesterone at or above the luteal phase level for a full 24-hour day.

Cyclic progesterone, for menstruating women of any age, means progesterone for the last two weeks of a menstrual cycle or of a month. Based on a randomized controlled trial, this treatment with cyclic progesterone increases spinal bone density and provides regular flow for women who have reversible (usually stress-related) reasons their periods have stopped or are far apart. Cyclic progesterone is also an essential therapy for premenopausal women with anovulatory androgen excess (AAE)(also called polycystic ovary syndrome [PCOS]) because it prevents endometrial cancer, slows the pulse frequency of luteinizing hormone (LH) thus decreasing testosterone production, provides regular menstrual-type flow and blocks the formation of the skin hormone that causes pimples and unwanted face hair. Cyclic progesterone is also a safe and effective treatment of perimenopausal cyclic night sweats (that occur around the time of flow for women whose cycles are still regular). In perimenopause, cyclic progesterone may also (especially if ibuprofen is also taken) help decrease heavy flow. Cyclic progesterone also helps with the sleep and premenstrual symptoms in perimenopause.

Early menopause (before age 40) can be treated with estradiol and cyclic or daily progesterone. This treatment is continued until a woman becomes age 50-52. With cyclic progesterone those women young enough to want regular flow will achieve it when estrogen is given in a long cycle (from the first to the 25th of the month) and progesterone from the 14 to the 27th. (Note—this is the only time ovarian hormone therapy is truly "replacement.")

Progesterone (taken daily) is effective treatment of menopausal hot flushes as shown by a CeMCOR randomized trial. Daily progesterone also significantly improves sleep in menopausal women (based on three controlled trials). In short, progesterone is effective therapy for women's menstrual cycle disturbances or perimenopause and menopause-related problems.

Join a Study:

Enrolment complete: Perimenopausal Hot Flush Study

Enrolment is now complete. Thank you for your interest.
CeMCOR is now recruiting Canadian women for this CIHR-funded randomized controlled trial to test whether oral micronized progesterone is more effective than placebo as therapy for hot flushes and night sweats in perimenopausal women.



Get Involved

Volunteer research participants are the heart of all CeMCOR research. Participants are invited to provide feedback on study processes, to learn their own results and at the end of a study, be the first to hear what the whole study found. Please become a CeMCOR research participant—you can contribute to improving the scientific information available for daughters, friends and the wider world of women.