Understanding menopause · Stage 1 of 3
Stage 01 of 3 · usually begins in your 40s
Perimenopause
The transition years.
Perimenopause is the stretch of years leading up to menopause. Your ovaries gradually make less estrogen, but the change isn't smooth — hormones swing up and down. Cycles become unpredictable and symptoms come and go. For most women this transition lasts four to eight years and ends 12 months after the final period.
The quick facts
Most women begin perimenopause in their mid-40s — though it can start as early as the late 30s.
What's happening in your body
Estrogen doesn't fall in a straight line — it swings as ovulation becomes irregular. Those swings drive many of the symptoms women notice first.
Symptoms you might notice
Symptoms come and go and change over time. No two women have the same experience — and your own experience can shift from month to month.
Good to know
Pregnancy is still possible during perimenopause. Until you've gone 12 months with no period, contraception may still be needed if you want to avoid pregnancy.
When to check in with your clinician
- Very heavy bleeding, or bleeding between periods
- Cycles shorter than 21 days or longer than 35 days that persist
- Symptoms that disrupt your sleep, work, or relationships
- Symptoms starting before age 40 — worth investigating early
General guidance only — your clinician can tell you what's right for your situation.