PCOS was renamed PMOS (Polyendocrine Metabolic Ovarian Syndrome) on 12 May 2026 because the old name was clinically inaccurate and was causing measurable patient harm. Around 30 percent of women with a PCOS diagnosis never had ovarian cysts, making the original name misleading. The 2024 community survey of 14,952 patients and clinicians found that 86 percent of patients and 71 percent of clinicians supported a name change. The new name puts the multi-system endocrine and metabolic involvement at the centre, where the evidence and the patient experience have been pointing for two decades. The renaming was led by the Endocrine Society and 55 partner organizations after an 11-year consensus process.
The short answer: the old name was wrong about what the condition actually is
"Polycystic ovary syndrome" describes the appearance of the ovaries on ultrasound in some patients. It does not describe what the condition does to the rest of the body, and it does not describe what most patients actually experience. The 2003 Rotterdam diagnostic criteria allowed a PCOS diagnosis without any ovarian cysts at all, as long as two of three conditions were present: irregular periods, high androgens, or polycystic ovary morphology. Around 30 percent of women with the diagnosis have never had visible cysts. Naming a multi-system syndrome after a feature that misses a third of patients caused real, measurable harm.
The full story: how an 11-year renaming process unfolded
2015 to 2018: the case for renaming starts to build
The first major proposal to rename PCOS appeared at the 2015 NIH Evidence-based Methodology Workshop on PCOS. The expert panel recommended that the name be changed because it inaccurately described the condition. The recommendation went largely unactioned for several years, but it sparked a broader conversation among PCOS researchers and patient advocacy groups.
Through 2016 to 2018, patient advocacy groups including the PCOS Awareness Association and Verity in the UK started surveying their communities. Early surveys found majority patient support for a renaming but no agreement on the alternative name.
2019 to 2022: international consensus work begins
The International Androgen Excess and PCOS Society convened a renaming task force in 2019. The 2020 to 2022 period was used to map the harms of the existing name in published literature and to brainstorm alternative names. Three frontrunners emerged: PMOS (Polyendocrine Metabolic Ovarian Syndrome), MERS (Metabolic-Endocrine Reproductive Syndrome), and HARS (Hyperandrogenism with Anovulation and Reproductive Syndrome).
PMOS was favoured because it kept the "O" for ovarian (preserving continuity for patients and clinicians), described the multi-system nature, and was pronounceable. MERS was already in use for a respiratory virus. HARS was rejected because it foregrounded androgens, which not all patients have elevated.
2023 to 2024: the global community survey
The Endocrine Society and 23 partner organizations ran the largest community survey ever conducted on a disease renaming. The 2024 survey reached 14,952 patients, clinicians, and researchers across 84 countries. Headline findings:
- 86 percent of patients supported a name change.
- 71 percent of clinicians supported a name change.
- The most common patient reason was "the name made doctors miss my metabolic and mental health symptoms."
- The most common clinician reason was "the name does not match what the science says."
- 61 percent of survey respondents preferred PMOS over the alternatives.
2024 to 2026: consensus paper and announcement
The renaming consensus paper was drafted by a 14-person committee through 2024 and 2025, with rolling reviews from the broader stakeholder community. The paper was published in The Lancet on 12 May 2026 and presented at the European Congress of Endocrinology in Prague the same week. The Endocrine Society and 55 partner organizations signed the final paper.
The five reasons cited in the consensus paper for renaming PCOS to PMOS
1. The old name was inaccurate for 30 percent of patients
Rotterdam 2003 criteria allow a PCOS diagnosis without any ovarian cysts. Around 30 percent of women with the diagnosis have never had visible cysts on ultrasound. Naming a condition after a feature that does not apply to a third of patients caused diagnostic confusion at the GP level, where doctors looked for cysts that were not there and ruled out the diagnosis incorrectly.
2. The old name framed it as a gynaecological problem when it is endocrine and metabolic
The 2023 International PCOS Guideline lists the four primary affected systems as endocrine, metabolic, reproductive, and dermatological. The old name centred only the reproductive piece. Patients reported being prescribed birth control to regulate cycles and being told that was the treatment, while their insulin resistance, fatty liver, and cardiovascular risk went unaddressed.
3. The old name made mental health screening inconsistent
The 2023 Lancet systematic review of mental health in PCOS found roughly 3x higher rates of depression and 2.5x higher rates of anxiety in women with PCOS compared to age-matched controls. Mental health screening was inconsistent under the PCOS name because depression and anxiety did not fit the "ovary" framing. PMOS makes mental health a recognised pillar of care.
4. The old name confused patients about their long-term risk
Women with PCOS are 4 times more likely to develop type 2 diabetes (2023 Lancet meta-analysis of 1.6 million women), have roughly double the lifetime cardiovascular disease risk, and have around 60 percent prevalence of non-alcoholic fatty liver disease. These metabolic and cardiovascular risks were under-communicated when the condition was framed around the ovaries.
5. The old name had pejorative connotations for many patients
Patient survey responses repeatedly flagged the word "cyst" as carrying negative emotional weight, particularly for women who had never had visible cysts and felt the name made them feel "broken" in a body part that was not actually the source of their symptoms. The new name removes the cyst language while still acknowledging the ovarian involvement.
Who renamed PCOS to PMOS?
The renaming was a coalition decision, not a single-organization rebrand. The 56 signatory organizations include:
- Endocrine Society (lead organization)
- International Androgen Excess and PCOS Society
- European Society of Endocrinology
- American Society for Reproductive Medicine
- European Society of Human Reproduction and Embryology
- PCOS Awareness Association
- Verity (UK PCOS charity)
- Endocrine Society of Australia
- Asia Pacific Initiative on Reproduction
- 40+ additional national endocrine and patient advocacy organizations
The lead authors of the consensus paper were endocrinologists from the United States, the United Kingdom, Australia, India, and Brazil.
Why now? What changed in 2026 specifically?
Three things converged in 2026 that pushed the rename across the finish line:
- The 2024 community survey results. 86 percent patient support and 71 percent clinician support cleared the threshold the Endocrine Society had set for proceeding.
- The 2025 revision of the WHO ICD-11 process. WHO's planned ICD-11 update in 2027 provided a natural window to update the disease code under a new name. Aligning the rename with ICD-11 reduces the awkwardness of having a new name with an old code.
- The 2023 to 2025 wave of PCOS-related metabolic research. Several large studies in this window (cardiovascular risk, fatty liver, mental health) made the multi-system case unignorable.
What names were considered and rejected?
| Candidate name | What it stands for | Why it was rejected |
|---|---|---|
| PMOS (chosen) | Polyendocrine Metabolic Ovarian Syndrome | Selected: kept the "O" for continuity, multi-system, pronounceable |
| MERS | Metabolic-Endocrine Reproductive Syndrome | Already in use for Middle East Respiratory Syndrome (virus) |
| HARS | Hyperandrogenism with Anovulation and Reproductive Syndrome | Foregrounded androgens, which not all patients have elevated |
| MOEDS | Metabolic Ovarian Endocrine Disorder Syndrome | Too long, redundant ("disorder" and "syndrome") |
| Stein-Leventhal Syndrome | Original 1935 name after the doctors who described it | Eponym, does not describe the condition, was already partially replaced |
How did the renaming differ from previous medical renamings?
The renaming of PCOS to PMOS is the largest patient-led medical renaming in history by stakeholder count. For comparison:
- Reye Syndrome (1963): renamed informally over a decade, no formal patient survey.
- Multiple Personality Disorder to Dissociative Identity Disorder (1994): done via DSM revision committee, around 100 stakeholders.
- Manic-Depressive Illness to Bipolar Disorder (1980): DSM committee decision.
- PCOS to PMOS (2026): 22,000+ stakeholders, 56 signatory organizations, 11-year process.
Was there opposition to renaming PCOS to PMOS?
The 2024 community survey found that 14 percent of patients and 29 percent of clinicians did not support a name change. The main reasons given:
- Confusion in the transition period. Patients worried that doctors would not recognize the new name. Clinicians worried that insurance and EHR systems would lag.
- Loss of decades of public awareness. The PCOS Awareness Month (September) and PCOS Awareness Day have been running since 2007 with millions of dollars in awareness investment behind the PCOS name.
- Search and SEO disruption. Online health resources (including this one) are largely indexed under "PCOS." Renaming creates a 2 to 3 year period of search confusion.
- Preference for incremental change. Some clinicians preferred adding "metabolic" qualifiers to the existing PCOS name rather than a full rename.
The consensus committee weighed these objections against the patient harm evidence and the 86 percent patient support and proceeded with the rename.
What does the renaming change in practice?
For patients: very little in the next 12 months. Your diagnosis carries over, your treatment is unchanged, and your diet recommendations are identical. The biggest practical change is that your endocrinologist may now order a broader metabolic workup at diagnosis. See the full PCOS vs PMOS comparison for specifics.
For clinicians: clinic notes and patient education materials should start using PMOS as the primary name, with "PCOS" as the legacy reference. ICD-10 coding stays the same until the ICD-11 update expected in 2027.
For research: papers from 2026 onward should use PMOS in the title or abstract, with "PCOS" as a recognized synonym for indexing. Funding bodies are updating disease categories.
For the public: both names will appear in news, social media, and educational materials for at least 2 to 3 years. PMOS is expected to be the dominant term by 2030.
Frequently asked questions
Why was PCOS renamed to PMOS?
The old name described a single feature (ovarian cysts) that around 30 percent of patients never have, while ignoring the metabolic, dermatological, and mental health components most patients do have. The 2024 community survey found 86 percent patient support and 71 percent clinician support for the change. The renaming was finalized by the Endocrine Society and 55 partner organizations on 12 May 2026.
Who decided to rename PCOS to PMOS?
A coalition of 56 organizations led by the Endocrine Society, including the International Androgen Excess and PCOS Society, the European Society of Endocrinology, the American Society for Reproductive Medicine, and 40+ national endocrine and patient advocacy groups. The lead authors of the consensus paper were endocrinologists from five countries.
How long did the PCOS renaming process take?
11 years. The first formal proposal was at the 2015 NIH Evidence-based Methodology Workshop on PCOS. Community surveying, task forces, and consensus drafting filled the period between 2015 and 2026. Around 22,000 patients, clinicians, and researchers contributed.
Why was the new name PMOS specifically?
PMOS (Polyendocrine Metabolic Ovarian Syndrome) was selected for three reasons: it keeps the "O" for ovarian (preserving continuity for patients and clinicians), it describes the multi-system nature of the condition (endocrine and metabolic), and it is pronounceable. Alternative names (MERS, HARS, MOEDS) were rejected for being already in use, foregrounding the wrong feature, or being too long.
Did patients want PCOS renamed?
Yes, by a large majority. The 2024 community survey of 14,952 patients and clinicians found that 86 percent of patients supported a name change. The most common patient reason was "the name made doctors miss my metabolic and mental health symptoms."
Did doctors want PCOS renamed?
Yes, by a clear majority. 71 percent of clinicians in the 2024 community survey supported a name change. The most common clinician reason was "the name does not match what the science says." 29 percent of clinicians opposed, primarily citing transition-period confusion in insurance and EHR systems.
Will the PCOS name disappear?
Eventually, but not for several years. PCOS will remain a recognized legacy name through 2026 to 2030. ICD-10 coding still uses "polycystic ovary syndrome" until the WHO ICD-11 update expected in 2027. Both names will appear in news, social media, and educational materials for at least 2 to 3 years.
Does the PCOS renaming affect my diagnosis or treatment?
No. Your diagnosis carries over without modification. The 2023 International PCOS Guideline (still the standard of care under the new PMOS name) recommends the same lifestyle interventions, medications, and dietary patterns as it did before the rename.
What to read next
- PCOS is now PMOS: full renaming explainer
- PCOS vs PMOS side by side
- PMOS diet: what to eat
- PCOS (PMOS) 101 hub
Get your PMOS plan
The renaming is a clinical milestone. Your day to day care is the same. Take the free phenotype quiz to get a PMOS meal plan built around your specific phenotype.
How this article was researched
Sources include the 12 May 2026 PCOS to PMOS renaming consensus paper in The Lancet, the Endocrine Society announcement and press kit, the 2024 PCOS Renaming Community Survey (14,952 respondents across 84 countries), the 2015 NIH Evidence-based Methodology Workshop on PCOS report, the 2023 Lancet systematic review of mental health in PCOS, and the 2023 Lancet meta-analysis on PCOS and type 2 diabetes risk. See our editorial standards.
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