Jerilynn C. Prior

Scientific Director, Centre for Menstrual Cycle and Ovulation Research
Degrees / Designations 

BA, MD, FRCPC, ABIM, American Board of Endocrinology Metabolism (ABEM)

Email Address 
604 875 5915
Mailing Address 
Vancouver General Hospital


Academic Appointment 
Body Locations and Systems 
Birth Control
Women's Health
Other Areas of Research 
Reproductive Health
Perimenopause hot flushes; night sweats

Jerilynn C. Prior BA, MD, FRCPC is a Professor of Endocrinology and Metabolism at the University of British Columbia in Vancouver, BC. She has spent her career studying menstrual cycles and the effects of the cycle’s changing estrogen and progesterone hormone levels on women’s health. She is the founder (2002) and Scientific Director of the Centre for Menstrual Cycle and Ovulation Research (CeMCOR). CeMCOR is actively researching women’s health and has a very accessible, informative website that receives on average between 3500-7000 page views per day ( She is also Director of the BC Centre of the Canadian Multicentre Osteoporosis Study (CaMOS – that is studying osteoporosis, fractures and bone mineral density and has followed over 9000 adult women and men across the country for over 19 years, plus about a 1000 younger women and men aged 16-24 for two years.

Dr. Prior has studied women’s menstrual cycles, perimenopause, menopause and the causes for and treatment of osteoporosis. She has shown that regular cycles (with enough estrogen) commonly do not produce sufficient progesterone (anovulation or short luteal phases). She first discovered and has since proven by meta-analysis that more versus fewer ovulatory disturbances within regular cycles are related to significant spinal bone loss in healthy women ages 20-45. She has shown in controlled trials that the ovarian hormone, progesterone, is effective treatment for menopausal hot flushes and, given cyclically increases bone mineral density in healthy women with hypothalamic amenorrhea. She also documented in a 3-month placebo-controlled trial that progesterone is safe for cardiovascular health. Dr. Prior is internationally known for her cumulative studies that now support progesterone as causing women’s increased bone formation through progesterone-specific osteoblast receptors. She has documented that estrogen levels, besides being unpredictable, are significantly higher than normal in perimenopause, the 3-10 years of changes before menopause. She is widely sought as a speaker for professional and lay audiences and is the author of the award-winning book Estrogen’s Storm Season: Stories of Perimenopause, a fiction book designed to inform and empower perimenopausal women. Estrogen’s Storm Season was a finalist in the 2006 Independent Publishers Book Awards for Health. Dr. Prior along with Susan Baxter PhD, sociologist/medical journalist, is author of The Estrogen Errors – Why Progesterone Is Better for Women’s Health (2009). This book aims to inform women of the decades of presumption and prejudice behind estrogen-centric women’s health dogma. She has authored scientific papers numbering over 270 and holds 6 patents. She is an Honourary Alumna of the University of British Columbia Faculty of Medicine and was awarded its Distinguished Medical Research Lecturer Award (2002). She has numerous other honours including the Ann Voda Lifetime Achievement Award in 2011 from the Society for Menstrual Cycle Research and the Knowledge Translation in Women’s Health Research Award from the BC Women’s Health Research Institute in 2017.