Perimenopause and Hormones: What Estrogen, Progesterone & Testosterone Actually Do.
I didn’t know.
Not in a vague, “I’d heard something about it” way. I genuinely did not know. My mom and I had never once discussed it. I don’t remember a single lesson in school. There was no conversation, no heads up, no preparation of any kind.
When I first heard the word perimenopause, I didn’t know it had anything to do with hormones. I didn’t know hormones were declining. I didn’t know there was a transition happening, or that it could start in your mid-30s, or that it would affect sleep and mood and weight and a dozen other things I’d been attributing to stress or age or just being busy.
I found out because I joined a beta group through re:spin — Halle Berry’s menopause education and support company. We met for an hour every week to discuss symptoms, go over protocols, share frustrations, and hold each other through this part of the journey. We had a coach there to guide us. And what I learned most from that group is that everyone’s experience was pretty unique — and that none of us had really been prepared for any of it.
This topic has only recently become more mainstream. Thankfully.
So let’s go back to the beginning.
Before you can recognize what’s happening in your body, it helps to understand what these hormones actually do when they’re working. Because once you know that — you might start connecting some dots. Maybe estrogen supports mood stability, and you’ve been having mood swings. Maybe progesterone is behind your sleep, and yours has been off for months. Maybe testosterone affects your energy and drive, and both have quietly gone flat.
That recognition is where it starts. Here’s what each one does.
Estrogen — the one everyone’s heard of, but not really
Estrogen is the hormone most people associate with being a woman. But its job goes far beyond your reproductive cycle.
Estrogen plays an active role in:
Bone density
Cardiovascular health
Temperature regulation
Skin moisture and collagen
Brain function and memory
Vaginal and urinary health
When it begins to fluctuate and decline, you might notice hot flashes. Night sweats. Joint stiffness that seems to appear out of nowhere. Skin that suddenly feels different. A brain that doesn’t feel as sharp as it used to.
A lot of women chalk this up to aging. Some of it is. But some of it is estrogen — and the two are not the same thing.
Women begin losing bone at a rate of 0.3–0.5% per year starting around age 40, a process that accelerates as estrogen declines.
Progesterone — the one behind your sleep and your sanity
This is the one that surprises most women.
Progesterone isn’t talked about the way estrogen is. But its decline may be responsible for some of the most disruptive symptoms of perimenopause — and it’s the one most likely to get misattributed to something else entirely.
Here’s the mechanism: progesterone is metabolized in the brain into a compound called allopregnanolone, which acts on GABA-A receptors — the same receptors targeted by anti-anxiety medications like benzodiazepines. This creates a natural calming effect on the nervous system.
When progesterone drops, that effect drops with it.
The result? Sleep that deteriorates even when you’re doing everything right. Anxiety that wasn’t there before. Mood swings that feel out of proportion. A low-grade edginess you can’t quite place.
Clinical research on micronized progesterone in perimenopausal women has found significant improvements in sleep quality, alongside reduced night sweats.
This is also why perimenopause symptoms so often get rerouted to mental health diagnoses. A woman comes in with anxiety and sleep disruption. She gets a prescription. And nobody asks what progesterone is doing.
I’m not dismissing mental health support. I’m saying the picture deserves to be complete.
Testosterone — the one nobody associates with women
Yes, women make testosterone. We have our entire lives. The fact that most of us were never told this is, honestly, absurd.
Testosterone supports:
Libido
Energy and motivation
Muscle mass and strength
Cognitive clarity and focus
Confidence and drive
Testosterone levels in women decline gradually with age — this decline is primarily age-related rather than triggered specifically by menopause, meaning it can start in your 30s and continue steadily. The years of perimenopause often coincide with the point at which this cumulative decline becomes noticeable.
You might notice it as fatigue that sleep doesn’t fix. Difficulty maintaining muscle no matter how consistently you train. Low libido that feels like something just went offline. A flatness in mood or motivation you can’t quite attribute to anything specific.
Because none of it is dramatic, it often doesn’t get investigated. And because testosterone is so heavily associated with men, it’s frequently not tested in women at all — and remains one of the most underexplored areas in women’s hormonal health.
They work as a system
Here’s the part that matters most.
These three hormones don’t operate independently. They interact. The balance between them — and the rate at which each fluctuates — shapes what your experience of perimenopause actually looks like.
This is why two women of the same age can have completely different symptoms. And why something that looks like one thing on the surface — anxiety, weight gain, exhaustion — may have more than one hormonal driver underneath it.
It’s also why “your labs came back normal” is not always the end of the conversation. Standard lab ranges don’t always reflect where your hormones sit relative to where you were functioning well.
What to do with this
I’m not going to tell you what decisions to make about your own hormones. That conversation belongs between you and practitioners who know your full picture.
What I will say: get educated before you feel urgency. Perimenopause has a way of creeping up quietly, and by the time you’re searching for answers, you’ve often already been in it for a while.
Ask your doctor to run a complete hormonal panel, not just a standard blood panel. If they’re not interested in the full picture, that’s useful information too. A certified menopause practitioner, a functional medicine doctor, or an OB-GYN who specializes in this transition will approach the data differently.
You don’t need to be in crisis to deserve this conversation.
What I want you to take away
Perimenopause is a three-hormone shift — estrogen, progesterone, and testosterone are all involved
Each hormone affects a different set of systems; the symptoms of their decline often look completely unrelated to each other
Progesterone converts to allopregnanolone in the brain, which has a calming effect — when it drops, so does that natural buffer against anxiety and sleeplessness
Testosterone is real in women, and its decline begins earlier than most people realize
Your experience is individual — there is no one version of this
You deserve practitioners who treat your case as the specific, complete picture that it is
One more thing
I’m working with a certified menopause practitioner and she’s been extremely knowledgable and helpful. She does both in-person and telehealth consultations, and if you’d like her information, just reply to this email or leave a comment. I’m happy to connect you.
Nothing in this newsletter is medical advice. I’m not a doctor. My goal is always to give you better context for the conversations you have with the people who can actually assess and support your health.
I’d love to hear where you are in this. Are you just starting to ask questions? Working with a specialist already? Leave a comment or reply directly — this is a conversation I want to keep having.
In health,
Tenaya
Sources
Exploring the effects of estrogen deficiency and aging on organismal homeostasis during menopause — PMC / NIH
Menopause — StatPearls, National Institutes of Health — NCBI Bookshelf
The GABA Connection: Hormones, Mood, and Menopause — FemmeBiome
Micronized Progesterone for Sleep: What the Research Shows — Dr. Beata Lewis MD
Testosterone levels decline with age, not menopause — Monash University / The Conversation
A Personal Prospective on Testosterone Therapy in Women — What We Know in 2022 — PMC / NIH
