What is perimenopause?
Perimenopause is the 2-10 year transition before menopause marked by cycle irregularity and rising FSH. Estradiol fluctuates wildly; progesterone declines steadily.
Full answer
Perimenopause is the hormonal transition preceding menopause, typically lasting 2-10 years. It begins with subtle cycle changes and ends 12 months after the final menstrual period. The hormonal signature is highly variable: estradiol fluctuates wildly with anovulatory cycles, progesterone declines steadily as ovulation becomes intermittent, and FSH rises progressively as ovarian reserve depletes. Symptoms — hot flashes, sleep disruption, mood lability, cognitive shifts, vaginal dryness, weight redistribution — reflect both the absolute hormonal decline and the rate of change. oMeds provider review uses estradiol, progesterone, FSH, and symptom mapping to guide bioidentical hormone optimization candidacy.
Educational. Not a substitute for individualized provider review.
- Estradiol — Primary source · oMeds
- Reviewed by Dr. Laura Purdy, MD, MBA · Clinical Director, oMeds · Last reviewed 2026-05-29