Welcome to Millwoods Acupuncture Centre

Millwoods Acupuncture Center
102, 2603 Hewes Way
Edmonton AB,   Canada

Phone: (780) 466-8683



Progesterone side effects


Data from: http://courses.washington.edu/bonephys/opestrogen.html#side

What about progesterone?

Progestins have been given to women who still have a uterus, because estrogen alone can increase the chance of endometrial cancer. However, in view of the recent studies showing increased risk of breast cancer and heart disease in women taking combination hormone therapy, the entire set of previous recommendations must be reconsidered.

Some studies have shown that progestins do not result in any additional benefits to the bone in women who are taking estrogen, either premenopausal (Prior, J. C., Hergenroeder, A. C.) or postmenopausal (Adachi, J. D., PEPI writing group(1996), Nand, S. L.). However, abstracts at the 2001 ASBMR meetings have shown increased bone density with norethindrone and (slightly) medroxyprogesterone acetate, when added to estrogen.

Progestins have several side effects, including bloating and depression. The beneficial effects of estrogen on the serum lipids are reduced with progestins (not as much with micronized progesterone as with medroxyprogesterone) as shown in the PEPI study (Barrett-Connor, E.). A study (Schairer, JAMA 2000; 283:485) of 46,355 women followed for an average of 10 years (during which time there were 2082 cases of breast cancer) showed that the overall risk for breast cancer was 3.9% per year in women not using hormones, 4.5% per year in those using estrogen, and 5.8% per year in those using both estrogen and a progestin.

Another study of a million women from England shows significantly more cases of breast cancer in women taking combination estrogen and progestin than in women taking estrogen alone. The risk per 1000 women over ten years was 5 extra cases of breast cancer from estrogen alone and 19 extra cases with combination.