Post #27

The Unusual Suspects: PMOS / PCOS

Crone Intelligence Briefing · Filed under: Prime Mimics & Hormonal Imposters

The Unusual Suspects

In this series I’ll be investigating the common culprits that mimic peri/menopause. Unfortunately, these imposters make it hard to navigate hormonal changes and to even discover whether you’re actually in peri/menopause in the first place.

Second offender in the dock is…

PMOS: Polyendocrine Metabolic Ovarian Syndrome
aka PCOS: Polycystic Ovary Syndrome

Well you guessed it, right from the start PMOS is a troublemaker. Not only is the condition a perimenopause imposter, it hasn’t even been honest about what it is.

Once known as PCOS due to the many ‘cysts’ that present themselves on the ovaries, it is now clearly inaccurate. Research published in The Lancet Journal demonstrated very effectively that it’s not just about the cysts but also the “disorder’s multisystem nature,” such as endocrine, metabolic, reproductive, psychological and dermatological features.

You might ask, what’s in a name? Well, misidentification has been damaging to sufferers — particularly in societies where fertility is paramount, since fertility challenges are often an aspect of PMOS — or has simply led to misdiagnosis. This is detrimental to the doctor-patient interaction (as if that’s not hard enough as it is), causing patients to not feel heard.

What is PMOS?

It’s a common, chronic and lifelong hormonal condition that affects 1 in 8 women and is caused by high androgen (or male) hormone levels. The results of this imbalance can be devastating and have knock-on health effects for sufferers, such as diabetes and heart disease.

Unfortunately, we’re dealing with yet another perimenopause mimic with remarkably similar symptoms to perimenopause: from periods and weight to hair and skin problems.

But let’s see why PMOS gets its reputation as Perimenopause Unusual Suspect #2.

The suspects compared

🦹 PMOS

Since young age periods have been irregular, missed or of varied heaviness
Midsection weight gain
Changes in head hair, male-pattern baldness, thinning and/or alopecia
Coarse body hair
Changes in skin including severe acne, Acanthis nigrans patches and skin tags
Mood disturbances: irritability and mood swings
Difficulty sleeping

🔥 Peri/menopause

Irregular, skipped or heavy periods
Midsection weight gain
Hot flashes and night sweats
Difficulty sleeping
Mood disturbances: irritability and mood swings
Adult acne
Thinning hair and coarse facial hair
Vaginal issues, dryness and UTIs

Once again there’s major overlap going on which adds to diagnosis delays and unnecessary patient suffering. I was alarmed but not surprised to read in the research articles below that many doctors are woefully under-educated on PMOS and how to interact with their patients about it.

Fat/weight shaming, or not taking the condition seriously, is too common and made for some uncomfortable reading.

What causes PMOS?

In the ovaries, LH (luteinizing hormone) and FSH (follicle-stimulating hormone) are doing a dance called the Two-Cell, Two-Gonadotropin Model. It regulates follicle growth (the egg sac) and estrogen production. The follicle has two different types of cells that react during this process.

LH stimulates theca cells (outer layer of follicle), causing them to produce androgens — the group of hormones that cause the development of male physical characteristics. But don’t be alarmed by this, men and women share male and female hormones.

The androgens diffuse into nearby granulosa cells (inner layer of follicle). FSH binds to the receptors on the granulosa cells to activate an enzyme called aromatase, which converts the androgens into estradiol (builds up the uterus ready for an incoming egg).

In PMOS this process gets out of balance resulting in:

A high LH:FSH ratio.
High LH leading to overproduction of androgens by theca cells.
An inability to convert androgens into estrogen.

So we get the plethora of PMOS symptoms.

How do you know if it’s PMOS or peri/menopause?

Targeted blood tests

I hate to sound like a cracked record but testing. And in this case testing through the PMOS lens first rather than perimenopause.

The FIRST test any doctor worth their salt (yeah, I know, a paradox) will perform here is for HIGH ANDROGEN LEVELS (hyperandrogenism). The levels of androgens change throughout life stages such as puberty, menopause, pregnancy etc.

The most famous androgen is testosterone. But it’s not the only one out there and the majority of androgens help to make other hormones. Androstenedione, DHEA (dehydroepiandrosterone), DHEAS (DHEA sulfate) and DHT (dihydrotestosterone) all help to make testosterone and estrogen.

Now you can see why this is such a hot Tango happening? They all need each other to function. Testing androgens will help determine PMOS. It’s not definitive but can help steer a doctor in the right direction (goodness knows they need it!).

SECONDLY, testing the rest of the hormones is just good practice to corroborate.

THIRDLY, glucose levels need testing, especially hemoglobin A1c (HbA1c), which measures average blood sugar levels over the past two to three months.

This is because women with PMOS are susceptible to insulin resistance, meaning they have more glucose in their blood. The pancreas releases insulin to help convert glucose back and forth from cells to tissues as and when needed. Insulin resistance happens when the cells start ignoring insulin.

A fasting insulin test can show where this is sitting and help build an overall picture.

LASTLY, testing for triglycerides and cholesterol is important because insulin resistance influences how the body processes fats.

High triglycerides, high LDL (low-density lipoprotein aka bad cholesterol) and low HDL (high-density lipoprotein aka good cholesterol) = Dyslipidemia = possible PMOS indicator (and risk for cardiovascular disease).

Bottom line

PMOS: high testosterone, HbA1c and insulin levels, high LDL and low HDL, imbalance between LH/FSH in a 2:1 or 3:1 ratio.

Perimenopause: high FSH and yoyo-ing estrogen, low testosterone.

⚠️ These are pieces of a diagnostic picture, not a DIY diagnosis. Talk to an actual medical professional — preferably one who listens.

Talking to the patient

Controversial as it sounds, it’s one of the simplest ways to determine a problem. Checking and tracking the regularity of periods and types of bleeding, frequency and heaviness can show whether ovulation is happening.

All very important since irregular periods are a key symptom of PMOS. There are other physical symptoms such as jawline acne and coarse facial hair that can be diagnosed by looking at the patient.

Ultrasound

Ultrasound is another useful tool. It can map the internal organs (womb and ovaries) and their blood supply and paint a picture. It reveals the size of the ovaries and whether they have follicles (no longer called cysts) or if the uterine lining (endometrium) has thickened.

Symptom overlap summary

🤝 Shared

Irregular periods, weight gain around the middle, thinning head hair, anxiety, irritability, sleep issues, fatigue, brain fog and acne.

🔥 Peri/menopause only

Hot flashes, night sweats, heavy prolonged periods, vaginal issues — dryness, atrophy, UTIs and urinary urgency — and joint aches.

🦹 PMOS only

Male-pattern hair growth — receding hairline and coarse hair on the face, chest and stomach — Acanthis nigrans dark patches on skin, cystic acne, insulin resistance and difficulty conceiving.

The PMOS plot twist

Women with PMOS experience menopause an average of 2–4 years later than those without the condition.

When the ovarian egg supply gets depleted to critically low levels that equals menopause. Women with PMOS have a larger number of immature follicles (eggs) in their ovaries.

They also have high levels of AMH (Anti-Müllerian Hormone), which tells the body to hold onto those follicles, keeping the reproductive window open longer. When periods are irregular and ovulation keeps skipping during reproductive years, the rate of follicle depletion slows down.

The consequences of this are:

An extended fertility window — it moves into the 30s and 40s and eggs are of a higher quality and quantity. Periods get more regular and can lead to fertility later on.
Perimenopause transition changes — the larger pool of eggs takes longer to deplete and draws out perimenopause.
Metabolic risk — dropping estrogen leads to worsening insulin resistance, faster abdominal weight gain, severe fatigue and high cholesterol.
Erratic bleeding — ovaries keep producing estrogen but progesterone tanks, leading to heavier, more painful and unpredictable periods.

Can menopause and HRT reverse PMOS?

Sadly no. PMOS is a chronic lifelong condition and throwing HRT at it or ending menstruation doesn’t affect that.

So let’s see what’s happening to a woman with PMOS. This is the timeline. In her 20s and 30s dealing with the debilitating aspects of PMOS is a real challenge and that includes the fertility journey and getting pregnant.

In her 40s a change towards metabolic issues (insulin resistance, cardiovascular concerns) occurs. As estrogen and progesterone levels ebb and flow, insulin resistance can worsen. Estrogen helps manage fat distribution.

Therefore, tracking the metabolic aspects of PMOS becomes critical after menopause and is something pointed out by researchers at Florida Atlantic University. Candy Wilson says we must reframe PMOS as a lifelong condition extending beyond the reproductive years, with cardiometabolic, pain and psychological risks that can persist or worsen.

BUT it’s not all doom and gloom because there are symptoms that improve with age. For example, the ovaries stop overproducing androgens and flooding the system. This means eggs get released from follicles more predictably, resulting in regular periods. There are fewer underdeveloped follicles on the ovaries. This mellowing out is discussed in the research papers below.

HRT will relieve perimenopause symptoms only, but it can help reduce the risk of type 2 diabetes and cardiovascular disease, both of which can develop when you have PMOS. When working out an HRT protocol, it’s good to bear in mind some women with PMOS can have abnormal thickness of the uterine lining.

PMOS is often treated with birth control because it’s a high-dose hormone therapy that suppresses androgen production. It also supports the uterus because all those irregular periods cause the uterine lining to thicken and can lead to endometrial cancer.

And then there are GLP-1s…

Research on GLP-1RAs (glucagon-like peptide-1 receptor agonists) is promising as they provide a multifaceted approach to managing PCOS, offering benefits across both metabolic and reproductive domains.

Good news for weight loss and diabetes prevention and potentially restoring a more regular hormonal pattern, supporting ovulation and a more consistent menstrual cycle.

Colorado woman Grace Hamilton joined a GLP-1 trial at CU Anschutz and found exactly this — a reversal in her PMOS symptoms. While this is big news (May 2026), it’s still pretty new so we’ll watch this space.

But even if there’s hope for PMOS sufferers (massive hoorah on that), I’m not letting PMOS super villain, arch enemy, get out of jail free!

THE CRONE'S VERDICT UNUSUAL SUSPECT #2:
GUILTY AS CHARGED!