Breast cancer

Breast cancer, although we think of it as one disease, it is really of many different types each with differing origins, response to treatment and risk factors. Women tend to be more worried about breast cancer than heart disease—most of us know some woman who has had breast cancer. Almost one woman of every nine white (western, privileged) women will get breast cancer in her lifetime—Asian women and those from less industrialized or more rural and poorer countries have lower breast cancer risks.There are a number of breast cancer risk factors over which we have little control. A very few women inherit breast cancer risks because of a close relative with it (mother, sister, cousin, grandmother, aunt) or because of having the gene for BRCA1 or BRCA2. However, 80% of women who develop breast cancer have no known family history. We also cannot control our age at menarche—it is a risk to start menstruating at younger than 11-12 years. Women who have menopause at age 55 or later are also at slightly greater risk for breast cancer.Although we talk of breast cancer prevention, screening mammograms, regularly doing breast self-examinations or having yearly health-care-provider breast examinations are finding a breast cancer that is already there. We also know many things that decrease our risks for breast cancer. These include maintaining a normal weight (BMI 18.5-24.9) throughout our lives, exercising moderately for 30 minutes a day, avoiding regular alcohol intake, using other barrier/vaginal spermicide contraception rather than COC, patch or ring and avoiding use of menopausal hormone therapy (OHT—combined estrogen and progestin/progesterone) especially in perimenopause or 5 years into menopause. However, if OHT is needed transdermal estradiol (patch, gel, or cream) with progesterone (rather than progestins like medroxyprogesterone) will not increase breast cancer risks (1).CeMCOR believes that silent ovulatory disturbances having normal amounts of estrogen (during regular cycles) but not normal amounts of progesterone, pose the major unrecognized risk for breast cancer. Ovulatory disturbances are common and not recognized (2) and are associated with other health risks such as bone loss (3). A combination of socially and emotionally supportive environments and healthy life styles with maintained ovulation is likely to lead to true breast cancer prevention.Reference List(1) Fournier A, Berrino F, Clavel-Chapelon F. Unequal risks for breast cancer associated with different hormone replacement therapies: results from the E3N cohort study. Breast Cancer Res Treat 2008 Jan;107(1):103-11.(2) Prior JC, Naess M, Langhammer A, Forsmo S. The point prevalence of ovulation in a large population-based sample of spontaneously, regularly menstruating women. The HUNT Study, Norway. Endocrine Society , OR 19-1 6573. 2013.(3) Li D, Hitchcock CL, Barr SI, Yu T, Prior JC. Negative Spinal Bone Mineral Density Changes and Subclinical Ovulatory Disturbances–Prospective Data in Healthy Premenopausal Women With Regular Menstrual Cycles. Epidemiol Rev 2014;36(137):147.

  • Dr. Prior’s Interviews on Fempower Health-The Podcast

    In 2021 and 2022, Dr. Jerilynn Prior was featured in four insightful podcast interviews conducted by Georgie Kovacs from Fempower Health. These episodes delve into crucial topics concerning women’s health, providing valuable information and expert perspectives.

  • Does taking progesterone pose an increased risk for breast cancer?

    I am using Prometrium 300 mg before bed, as it is the only intervention I have tried (pharmaceutical and naturopathic) that has worked.  I am concerned about breast cancer, and can’t seem to find any reliable information about how bio identical progesterone would affect risk. If you are able to shed light on this, it is much appreciated.

  • Progesterone is NOT a Progestogen/Progestin— It’s Estrogen’s Unique Biological Partner

    This article was originally published in our e-newsletter. by Dr. Jerilynn C. Prior, Scientific Director, Centre for Menstrual Cycle and Ovulation Research Current lay and medical women’s health literature considers progesterone, the human hormone made by women’s ovary in the same category as its synthetic, “knock-offs”. “Progestogens. . .include both endogenous progesterone and synthetic progestogens…

  • Beyond “Estrogen Deficiency”—news from Women’s Health Initiative

    The USA’s National Institutes of Health just announced that the Estrogen arm of the Women’s Health Initiative was stopped early (1). Estrogen treatment in women who had undergone hysterectomy was associated with neither benefit nor harm for heart disease and caused a 40% increase in stroke (1). No one can ever again say that estrogen…

  • The Death of Hormone Replacement Therapy — Why and how to use Ovarian Hormone Therapy

    A response to the cancelled Women’s Health Initiative study and call for a healthier look at menopause Dr. Jerilynn C. Prior, Scientific Director of the Centre for Menstrual Cycle and Ovulation Research, has never advocated the use of hormones as an ongoing “replacement” for menopause. She does not feel that menopause is a medical condition…