Polycystic ovary syndrome (PCOS), now called polyendocrine metabolic ovarian syndrome (PMOS, or SMOP in French)1, is a common hormonal disorder2. The World Health Organization estimates that it affects 10 to 13% of women of reproductive age3, and that a large proportion of the people who have it do not know it4. Its signs vary a great deal from one person to another5.

This page brings together pointers to help you understand the condition, prepare for an appointment and find the sources. It does not replace medical advice.

A name that is changing

In May 2026, an international consensus adopted a new English name: polyendocrine metabolic ovarian syndrome, or PMOS6. The old name suggested “cysts” on the ovaries, which are not a feature of the syndrome7. The new name highlights its three dimensions: hormonal, metabolic and ovarian8.

In French, the most common form in institutional sources is “syndrome métabolique ovarien polyendocrinien”, or SMOP1. A variant, SOMP, is also in circulation9. The old and new names will coexist for several years10, and the change does not alter the diagnostic criteria11.

We write “PCOS (PMOS)”: “PCOS” is still the word most people search for and the one that appears in many medical reports. All about the new name.

Where to start

Our reference sources

We rely first on the 2023 international guideline, coordinated by Monash University and published in several medical journals, on the World Health Organization fact sheet, and on the public French-language information from the French Assurance Maladie, Inserm and the Geneva University Hospitals.

This basic information is freely available, and that is how it should be. The Geneva University Hospitals (HUG), for example, offer a brochure you can download without registering12. Our role is to make it easier to use: vocabulary explained, printable tools, and every statement linked to its source. See the full bibliography and how we work.

Sources for this page

Each number leads to a neutral statement and to the documents that support it. We summarise these sources in our own words; the links open the original documents.

  1. 1

    In French, the form most used by the institutional sources consulted is “syndrome métabolique ovarien polyendocrinien” (SMOP), used in particular by Inserm, by the Assurance Maladie (with slightly different punctuation) and by RTS in Switzerland.

    Established fact · checked on 18 October 2026

    An observation of usage as of 18 October 2026, not an official terminology: no position from the HAS, the CNGOF or Swiss learned societies had been found by that date.

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  2. 2

    The WHO describes a common hormonal disorder in which higher-than-normal androgen levels can lead to irregular periods, ovulation disorders, infertility, excessive hair growth and/or acne.

    Established fact · checked on 18 October 2026

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  3. 3

    The WHO and the international guideline estimate that 10 to 13% of women of reproductive age are affected.

    Established fact · checked on 18 October 2026

    Estimates vary depending on the criteria and the sources (Ameli: 6 to 13%; Lancet publication: one woman in eight).

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  4. 4

    According to the WHO, up to 70% of the people affected are thought to be undiagnosed.

    Established fact · checked on 18 October 2026

    Global WHO estimate.

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  5. 5

    The signs and symptoms vary from one person to another, are not always present at the same time and can change over time.

    Established fact · checked on 18 October 2026

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  6. 6

    An international consensus process selected “polyendocrine metabolic ovarian syndrome” (PMOS) as the new English name for the syndrome previously called “polycystic ovary syndrome” (PCOS).

    Established fact · checked on 18 October 2026

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  7. 7

    The “cysts” suggested by the old name are not a feature of the syndrome: the appearance of the ovaries on ultrasound corresponds to follicles whose development has stopped, and cysts are not needed for the diagnosis.

    Established fact · checked on 18 October 2026

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  8. 8

    The terms “polyendocrine”, “metabolic” and “ovarian” were chosen to reflect the involvement of several body systems: the new name drops the mention of cysts and describes a dysfunction that is at once hormonal (endocrine), metabolic and ovarian.

    Expert consensus · checked on 18 October 2026

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  9. 9

    The French-language documents distributed by the Monash team use another form: “syndrome ovarien métabolique polyendocrinien” (SOMP).

    Established fact · checked on 18 October 2026

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  10. 10

    The leaders of the consensus plan a three-year transition period during which the two names coexist; the 2028 update of the international guideline is to use only the new name.

    Established fact · checked on 18 October 2026

    The Lancet abstract mentions a transition period without specifying its length; the length comes from the Monash documents.

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  11. 11

    According to the team that coordinates the international guideline, the name change does not alter the content of the 2023 recommendations, the diagnostic criteria or the approach to care.

    Established fact · checked on 18 October 2026

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  12. 12

    The Geneva University Hospitals (HUG) offer an information brochure on PCOS that can be downloaded without registering, in an edition from November 2020 reprinted in October 2022.

    Established fact · checked on 18 October 2026

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