In Part 1 of our menopause series, we explore two fundamental questions: Why does menopause exist, and what physiologic changes drive the menopausal transition?
Topics include:
Definitions of perimenopause, menopause, and postmenopause
Why humans are unusual among mammals in having a long post-reproductive lifespan
The Mother and Grandmother hypotheses
Chimpanzee and whale comparisons
Oocyte development and follicular depletion
AMH, inhibin B, FSH, and ovarian aging
The hypothalamic-pituitary-ovarian axis
Why menstrual cycles become irregular during perimenopause
The physiologic foundation for menopausal symptoms
This episode lays the groundwork for future discussions of vasomotor symptoms, mood changes, hormone therapy, and modern menopause management.