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Hormones & cycle 2 min read

PCOS: symptoms, causes and diagnosis

PCOS — renamed polyendocrine metabolic ovarian syndrome (PMOS) in May 2026 — is a common hormonal condition affecting 10 to 13% of women of reproductive age, combining irregular cycles, androgen excess (acne, increased hair growth) and often insulin resistance. Diagnosis rests on a set of clinical and biological criteria rather than any single test — an ultrasound alone never settles it.

Macro texture of densely clustered cells standing for polycystic ovarian morphology

PCOS is the most common hormonal condition in women of reproductive age and one of the most frequently missed — the WHO estimates that up to 70% of affected women are undiagnosed. Part of the reason is in the name: it points at the ovaries, when the condition reaches well past them.

What PCOS is, and what it is now called

Polycystic ovary syndrome affects 10 to 13% of women of reproductive age. In May 2026 an international consensus published in The Lancet renamed it polyendocrine metabolic ovarian syndrome — PMOS — to reflect a reality that reaches well beyond the ovaries. The rename changed the name and nothing else: the diagnostic criteria and the management stayed as they were. Both terms are expected to coexist through a three-year transition, up to the 2028 international guideline update. If you see either on a medical document, it describes the same clinical reality.

The most frequent symptoms

Irregular cycles, or no regular ovulation. Hormonal acne, often on the lower face. Increased hair growth on the face or chest, driven by androgen excess. Weight gain or difficulty losing weight, tied to the insulin resistance frequently found alongside. Male-pattern hair loss in some cases. How intense these are and how they combine varies enormously between women — some have very few visible symptoms at all.

How the diagnosis is made

Diagnosis rests on at least two of three criteria — the Rotterdam criteria, still in force: irregular cycles or absent ovulation; clinical or biological signs of androgen excess; and polycystic ovarian morphology. Since 2023 the international guideline allows that third criterion to be established by a blood marker, anti-Müllerian hormone, as an alternative to ultrasound in adults — one or the other, never both, to avoid over-diagnosis. And it never suffices on its own: many women with the diagnosis do not have it, which is part of why the word polycystic was misleading and why the name was changed.

What it means beyond the cycle

Insulin resistance is frequently present rather than something that arrives later, and PMOS carries a raised long-term risk of type 2 diabetes. That is why the international guideline asks for glycaemic status to be assessed at diagnosis, and why follow-up should reach past the gynaecological question — precisely what the new name is trying to capture: an approach that takes the metabolism into account, not only the cycle.

  • Do not rely on an ultrasound alone to confirm or rule out PCOS — it is one criterion out of three.
  • Track your cycles, your skin and your hair growth over several months before a consultation.
  • If PCOS is diagnosed, ask for follow-up that includes the metabolic side, not only the cycle.
  • Do not be thrown by seeing the older name on medical paperwork — it is the same clinical reality during the transition.

Reviewed by the OVEA medical committee

Frequently asked questions

Can I have PCOS without visible cysts on an ultrasound?

Yes, and it is common — the ovarian appearance is only one criterion of three, it can now be established by an AMH blood test instead of an ultrasound in adults, and many diagnosed women do not have it at all.

Does PCOS stop me getting pregnant?

It makes ovulation more irregular or less frequent, but does not systematically prevent natural pregnancy; support is available if needed.

How common is PCOS?

It affects 10 to 13% of women of reproductive age, making it the most frequent hormonal condition in that population — and the WHO estimates that up to 70% of cases go undiagnosed.

Why does PCOS involve insulin?

Insulin resistance is frequently associated with it, which is why weight can be harder to manage and why follow-up should cover metabolism too.

Has PCOS been renamed?

Yes — a May 2026 international consensus published in The Lancet renamed it polyendocrine metabolic ovarian syndrome (PMOS); the criteria and the management did not change, and both names remain in use through the transition.

Sources & method

This article was written from reference medical guidelines and publications, then reviewed by the OVEA medical committee.

  1. Teede HJ, Piltonen T, Dokras A, et al. Polyendocrine metabolic ovarian syndrome, the new name for polycystic ovary syndrome: a multistep global consensus process. The Lancet 2026;407(10545):2329–39. DOI: 10.1016/S0140-6736(26)00717-8
  2. Teede HJ, Tay CT, Laven JJE, et al. Recommendations from the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. J Clin Endocrinol Metab 2023.
  3. World Health Organization. Polycystic ovary syndrome — fact sheet (2026).
  4. Inserm. Syndrome des ovaires polykystiques (SOPK) / Syndrome métabolique ovarien polyendocrinien (SMOP) — dossier d’information (2026).
  5. Assurance Maladie. Symptômes, diagnostic et évolution du syndrome des ovaires polykystiques. Ameli.fr (2026).
  6. ESHRE. Position statement on the PCOS name change (2026).
  7. Endocrine Society. PCOS name change announcement — three-year transition to full implementation in the 2028 International Guideline update (2026).

Health note

This content is educational and does not replace a diagnosis, a treatment or a consultation with a health professional. If symptoms persist or worry you, see a doctor.

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