What Is PCOS, and Why Your Doctor Probably Hasn't Diagnosed It
A fascinating conversation on the Huberman Lab Podcast with Dr. Tais Aliabati had me dive deep into Women's Reproductive Health. Over the next few posts, I’ll share some key takeaways from that episode and beyond, which I hope can help you find a deeper understanding of your own body.
If you've been told your periods are just 'a bit irregular,' that your acne is stress-related, or that the hair you're losing is just hormonal, this might be one of the most important things you read today. PCOS, or polycystic ovary syndrome, is the most common hormone disorder in women of reproductive age. It affects roughly 1 in 7 women in the US, and potentially 1 in 5 in some populations worldwide. And yet, studies suggest that between 70 and 90 percent of cases go undiagnosed.
That's not a small gap. That's millions of women walking around with a condition that is treatable, whose symptoms are being written off as stress, weight, or just being a woman. Here's what PCOS actually is, how to recognize it, and what you can do if you think you might have it.
First, the name is misleading
Polycystic ovary syndrome suggests there are cysts on your ovaries. There usually aren't. That naming confusion is one of the reasons so many doctors miss it: a patient comes in, gets an ultrasound, the doctor sees no cysts and says, 'You don't have PCOS.' That's not how it works.
What the ultrasound is actually looking for is a specific pattern: 20 or more small follicles arranged in a string-of-pearl formation. These aren't cysts. They're follicles that started developing but never fully matured and ovulated. Why? Because of a hormonal disruption happening upstream in the brain.
What's actually going wrong
The root of PCOS is a disruption in the brain-pituitary-ovary axis, the signalling chain your body uses to regulate your cycle. Normally, your hypothalamus releases a hormone called GnRH in a slow, rhythmic pulse. In women with PCOS, this firing speeds up, which throws off the balance between two key hormones: FSH (follicle-stimulating hormone) and LH (luteinizing hormone).
When LH rises, and FSH falls, the ovaries get an abnormal signal. Instead of maturing one dominant follicle and releasing it at ovulation, the ovaries start overproducing androgens, a group of hormones that includes testosterone. These elevated androgens then cause the follicles to freeze before they can fully develop.
No ovulation means no progesterone surge. No progesterone surge means irregular or absent periods. And all those stalled follicles? They stay in the ovary, which is what creates that characteristic ultrasound pattern. This is the core mechanism. But it doesn't happen in isolation.
Insulin resistance makes it worse
About 80 percent of women with PCOS have some degree of insulin resistance, including women who are lean and otherwise healthy. This is important because insulin resistance is not just a weight issue. It's a cellular issue: your cells don't respond normally to insulin, so blood glucose stays high, and the pancreas pumps out more insulin to compensate.
That excess insulin does several things that make PCOS symptoms worse. It tells the ovaries to produce even more androgens. It suppresses a protein called sex hormone-binding globulin, which normally grabs free testosterone from the blood and keeps it in check. When SHBG drops, free testosterone rises, which worsens acne, hair loss, and facial hair.
High insulin also drives the storage of visceral fat, which is the fat that surrounds your organs, not the fat just under your skin. Visceral fat releases inflammatory compounds that further worsen insulin resistance and stimulate more androgen production. It becomes a self-reinforcing loop.
This is also why some women with PCOS feel like they gain weight by looking at food, or struggle for years with diet and exercise without results. The underlying metabolic issue hasn't been addressed, and no amount of calorie restriction fixes a hormonal disruption.
How to recognize it: the actual diagnostic criteria
PCOS is diagnosed when you meet at least 2 of these 3 criteria:
Signs of elevated androgens: acne that persists beyond your teens, oily skin, facial or body hair growth, or noticeable hair thinning at the scalp in a male-pattern distribution
Ovulatory dysfunction: irregular cycles (longer than 35 days, fewer than 8 periods per year, or just unpredictable month to month)
PCOS-pattern ovaries on ultrasound, or a high AMH (anti-Mullerian hormone) level on a blood test
You do not need all three. You need two.
This is where many diagnoses fall through the cracks. A doctor checks testosterone, finds it normal, and rules out PCOS. But elevated testosterone in the blood is not a diagnostic requirement. Many women with PCOS have normal testosterone on a standard panel. What matters is whether you have the symptoms, not just the lab value.
Similarly, a normal pelvic ultrasound does not rule out PCOS. There are four recognized subtypes, and one of them involves completely normal-looking ovaries on ultrasound.
PCOS looks different in different women
Because there are four distinct subtypes, PCOS doesn't always look the same from person to person. The classic presentation involves all three criteria together: PCOS-pattern ovaries, androgen symptoms, and irregular periods. But some women have all of those without elevated testosterone in their bloodwork. Some have regular-looking cycles while still not ovulating consistently. Some have no androgen symptoms at all. This variability is part of why it gets missed.
What PCOS does to fertility
Between 70 and 80 percent of women with PCOS don't ovulate regularly, even when they appear to have regular periods. A cycle can happen because of estrogen withdrawal, not because ovulation occurred and progesterone followed. That distinction matters enormously if you're trying to conceive.
It also matters for egg quality. Women with PCOS often have high AMH levels and high follicle counts, which sounds reassuring. But high AMH in the context of PCOS reflects a large number of stalled, low-quality follicles, not a healthy reserve of viable eggs. This is a critical nuance: if you've been told your egg count looks great and no one checked whether you have PCOS, that reassurance may be incomplete.
Signs that PCOS might be the bigger picture
Beyond the diagnostic criteria, PCOS often comes with a broader cluster of experiences that get dismissed individually but tell a coherent story together:
Acne that persists into your 20s or 30s and hasn't responded well to standard treatments
Hair loss or noticeable thinning at the scalp
Hair removal on the face, chin, or body that keeps coming back
Difficulty losing weight despite diet and exercise changes
Anxiety, depression, or mood swings that feel disproportionate
Irregular, unpredictable periods, or periods you can't track reliably
A history of being told you have an eating disorder when the behaviour might be driven by metabolic signals, not psychology
If several of those resonate, the answer isn't more willpower or a different diet. It's an accurate diagnosis.
What to ask your doctor
You don't need to wait for your doctor to bring this up. You can go in informed and ask directly.
Ask for an AMH blood test
Ask for a full hormone panel, including testosterone, FSH, LH, and insulin
Ask for a pelvic ultrasound to assess ovarian morphology
Ask whether your cycle history and symptoms are consistent with PCOS
A free, research-informed PCOS likelihood quiz is also available at OVI.com, developed by Dr. Tais Aliabati, OB/GYN and women's health specialist. It won't replace a clinical diagnosis, but it can give you useful language and context before your appointment.
What happens after diagnosis
PCOS isn't curable, but it is highly manageable. The most effective approaches target the underlying drivers, particularly insulin resistance and inflammation, rather than just masking symptoms with birth control.
First-line options include lifestyle changes (regular meals, strength training, walking after meals, quality sleep), targeted supplements like myo-inositol and vitamin D, and, in some cases, prescription metformin or GLP-1 medications. Birth control can help manage symptoms like acne and cycle irregularity, but it doesn't address the root cause and isn't the right first answer for everyone.
The goal is to lower insulin, reduce androgen production, restore ovulation, and break the inflammatory loop. That is achievable, and for many women, it makes an enormous difference.
The bottom line: PCOS is the most common hormone disorder in women, affects roughly 1 in 7, and the majority of cases go undiagnosed. If you've been dismissed, told your symptoms are normal, or cycled through treatments that never quite worked, pushing for a proper workup is worth it. Knowing what's actually happening is the first step toward fixing it.
Scientific References
1. Bozdag, G., et al. (2016). "The prevalence and phenotypic features of polycystic ovary syndrome: a systematic review and meta-analysis." Human Reproduction, 31(12), 2841-2855.
2. March, W.A., et al. (2010). "The prevalence of polycystic ovary syndrome in a community sample assessed under contrasting diagnostic criteria." Human Reproduction, 25(2), 544-551.
3. Azziz, R., et al. (2004). "The prevalence and features of the polycystic ovary syndrome in an unselected population." Journal of Clinical Endocrinology and Metabolism, 89(6), 2745-2749.
4. Dunaif, A. (1997). "Insulin resistance and the polycystic ovary syndrome: mechanism and implications for pathogenesis." Endocrine Reviews, 18(6), 774-800. (Foundational paper on insulin resistance in PCOS.)
5. Franks, S. (1995). "Polycystic ovary syndrome." New England Journal of Medicine, 333(13), 853-861.
6. Dewailly, D., et al. (2014). "Definition and significance of polycystic ovarian morphology: a task force report from the Androgen Excess and Polycystic Ovary Syndrome Society." Human Reproduction Update, 20(3), 334-352.
7. Teede, H.J., et al. (2018). "Recommendations from the international evidence-based guideline for the assessment and management of polycystic ovary syndrome." Human Reproduction, 33(9), 1602-1618.
8. Rotterdam ESHRE/ASRM-Sponsored PCOS Consensus Workshop Group. (2004). "Revised 2003 consensus on diagnostic criteria and long-term health risks related to polycystic ovary syndrome." Fertility and Sterility, 81(1), 19-25.