Let me tell you what’s really happening in your body—because what you’ve been told is probably wrong.
The Myth of “Declining Estrogen”
You’ve heard it a hundred times: menopause is about declining estrogen. It sounds simple. It sounds orderly. It’s also misleading.
Here’s the truth: during perimenopause, your estradiol levels often run 20-30% HIGHER than they did in your younger yearsPrior JC. Perimenopause: The Complex Endocrinology of the Menopausal Transition. Endocrine Reviews. 1998;19(4):397-428.—in some cycles, spiking even higher than that. Then they crash. Then they spike again.
Your estrogen doesn’t politely decrease. It swings—sometimes higher than it’s ever been, sometimes plummeting to nearly nothing, sometimes changing dramatically within a single week.
This is why you feel like you’re going crazy. You’re not. Your hormones are genuinely doing something wild.
The Players in This Drama
Estradiol (E2) — The Lead
This is your primary estrogen, produced by the follicles in your ovaries. During perimenopause:
- It doesn’t decline in a straight line—it fluctuates wildly
- Some cycles, it spikes higher than it ever did in your twenties
- It affects over 400 different tissues in your body—your brain, bones, heart, skin, eyes, and more
- The fluctuation itself causes symptoms, not just the level
Progesterone — The Calming Voice That Goes Quiet
Progesterone is produced after you ovulate. It’s the hormone that balances estrogen, and it has a profoundly calming effect—it works on the same brain receptors as anti-anxiety medications.
Here’s the problem: as perimenopause progresses, you ovulate less often. Some cycles, you don’t ovulate at all. No ovulation means no progesterone. So you end up with high, erratic estrogen and little to no progesterone to balance it.
This is what some call “estrogen dominance”—not too much estrogen in absolute terms, but too much estrogen relative to progesterone. It’s why you might feel more anxious, more irritable, more emotionally raw than ever before.
FSH (Follicle-Stimulating Hormone) — The One That Won’t Stop Shouting
Your pituitary gland produces FSH to tell your ovaries to develop follicles. When your ovaries start responding less, your pituitary shouts louder—more FSH.
What you should know:
- FSH starts rising about 6 years before your final period
- After menopause, your FSH will be about 14 times higher than a man’s
- A single FSH test tells you almost nothing—levels swing dramatically from day to day, week to week
- Emerging research suggests FSH itself may directly affect your mood, independent of estrogen
LH (Luteinizing Hormone) — The Ovulation Trigger
LH surges to trigger ovulation. During perimenopause, it also rises overall and may contribute to cognitive symptoms—particularly verbal memory and word-finding.
The Supporting Cast
Inhibin B declines early in the transition. It normally tells FSH to calm down, so when it drops, FSH rises faster.
AMH (Anti-Müllerian Hormone) reflects your remaining egg supply. It’s actually a better predictor of how close you are to menopause than FSH—but most doctors don’t test it routinely.
Where Are You in This Journey?
Researchers have mapped out the stages of this transition. It’s called STRAW+10Harlow SD, et al. Executive Summary of the Stages of Reproductive Aging Workshop +10. Menopause. 2012;19(4):387-395., and while bodies don’t follow charts perfectly, it can help you orient yourself:
Early Perimenopause (Stage -2): Your cycles start varying—maybe 7 or more days different from your usual. You might not notice much else yet, or you might already be feeling the shifts.
Late Perimenopause (Stage -1): You start skipping periods—60 days or more between cycles. This is when vasomotor symptoms often begin in earnest. This stage typically lasts 1-3 years.
Early Postmenopause (Stage +1): It’s been 12 months since your last period. You’re officially “through.” But symptoms often continue—sometimes for years.
Late Postmenopause (Stage +2): You’re well past the transition, though some symptoms may persist. For many women, things do stabilize and ease here.
Understanding this isn’t just academic. It explains why some support strategies work and others don’t. It explains why stabilizing your hormones—even at lower levels—often helps more than trying to replace them at “youthful” levels. It explains why what works for your friend might not work for you.
Your body is doing something complicated. Now you know what it is.