Culture and menstruation the ideal of synchronised tidal, lunar, menstrual and seasonal periodicities whose overall harmony (it is believed) confers spiritual power and fertility. To many, such cultural associations appear persuasive in view of the fact that in humans, the menstrual cycle quite closely approximates the moon's 29.5-day synodic cycle, unlike in chimpanzees (~36 days) or bonobos (~40 days). Statistical information from hunter gatherers is lacking, but where large-scale western studies focus on women's peak reproductive years—removing outlier values—the cycle length gravitates around 29.1–29.5 days, while the figure for women in their thirties shortens toward 28 days. In no extant human population has
Centre for Menstrual Cycle and Ovulation Research stated that its research shows overall that regular menstrual cycles with ovulation help prevent osteoporosis, breast cancer, and heart disease. Dr. Prior has called menstrual cycles "a vital sign". CeMCOR does not conduct research funded by the pharmaceutical industry. Centre for Menstrual Cycle and Ovulation Research The Centre for Menstrual Cycle and Ovulation Research (CeMCOR) is a health research centre in Vancouver. According to the University of British Columbia, CeMCOR is the only centre in the world that focuses on ovulation and the causes and consequences of ovulation disturbances. CeMCOR is known for research on progesterone-only therapy for menopausal hot