PCOS has been renamed PMOS: what changed and what it means for you

Yes, polycystic ovary syndrome (PCOS) has a new name: polyendocrine metabolic ovarian syndrome (PMOS). It was agreed through an international consensus process published in The Lancet in 2026, led from Monash University in Australia with 56 patient and professional organisations, including the Endocrine Society. It is the same condition under a more accurate name. How it is diagnosed and treated did not change on the day the paper came out.

The changeover is gradual by design. The Lancet paper sets out a managed transition period of three years, and the Endocrine Society says the new name will be fully built into the International Guideline at its 2028 update. Until then you will meet both terms, sometimes in the same week: the NHS and Mayo Clinic already use PMOS, while many medical records, forms, and some guidance still say PCOS.

If you already have a PCOS diagnosis, it still stands. The rename is meant to change how the condition is understood, moving the focus from the ovaries alone to hormones and metabolism, not to unsettle a diagnosis you already have.

A clinician going through paperwork with a woman at a desk. Photo by RDNE Stock project on Pexels.

Why was PCOS renamed?

The short answer is that the old name described a feature the condition does not reliably have. "Polycystic" suggests the ovaries fill with cysts. According to the Lancet consensus, pathological ovarian cysts are not increased in the condition. What an ultrasound often shows instead is a collection of small follicles whose development has stalled, which is not the same as a cyst. The Endocrine Society reports that a related paper by the same research group found no increase in abnormal ovarian cysts, and Mayo Clinic now states that large ovarian cysts are not a sign of PMOS.

The name also hid most of the picture. The Lancet authors describe a condition involving several hormone systems, including higher androgens and insulin resistance, with links to type 2 diabetes and cardiovascular risk. The NHS lists depression, anxiety, tiredness and skin changes among its symptoms alongside irregular periods and difficulty getting pregnant. The authors argue the misleading name contributed to delayed diagnosis, fragmented care and stigma, and they estimate that up to 70% of people with the condition remain undiagnosed.

Calls to rename it are not new. A 2012 US National Institutes of Health workshop recommended a change. In a 2023 international survey reported in eClinicalMedicine, 85.6% of patients and 76.1% of health professionals agreed the name should change, and terms such as "endocrine" and "metabolic" had the strongest support.

What does PMOS stand for?

Each part of the new name points to a feature the Lancet consensus describes:

Part of the name	What it reflects
Polyendocrine	Several hormone systems are involved, including raised androgens and insulin
Metabolic	Insulin resistance and higher long-term risk of type 2 diabetes and cardiovascular problems
Ovarian	Irregular or absent ovulation, and many small follicles on ultrasound in some people
Syndrome	A cluster of features that varies from person to person, not a single test result

The consensus deliberately chose an evolution of the old name rather than a completely new one. Keeping "ovarian syndrome" and a similar four-letter acronym was intended to make the switch recognisable to patients and clinicians, so the condition does not look like a newly discovered disease.

What has not changed

The name changed. The medicine around it, for now, has not.

Diagnostic criteria: adults still need at least two of three features after other causes are excluded: irregular or absent ovulation, signs of higher androgens on examination or blood tests, and polycystic ovaries on ultrasound or a raised anti-Müllerian hormone (AMH) level.
Diagnosis in teenagers: adolescents need both irregular cycles and higher androgens, because ovaries in the years after puberty can look polycystic anyway.
Your existing diagnosis: Yale Medicine says it remains valid and no immediate action is needed because of the rename.
Treatment options: the NHS still lists hormonal contraception for irregular periods, metformin, medicines for unwanted hair growth and acne, and fertility treatment where needed.
There is still no cure: the NHS is explicit that treatments and lifestyle changes help symptoms but do not cure the condition.

A rename is not a re-diagnosis: if your records say PCOS, you do not need a new appointment just because the name changed.

Why you will see both names for a while

Public health pages have moved faster than the systems behind them. This is the picture when checked in October 2026:

Where you look	What you are likely to see
NHS, Mayo Clinic, Johns Hopkins Medicine	PMOS, with a note that it used to be called PCOS
WHO fact sheet, ACOG patient FAQ	Still PCOS
Medical records, prescriptions, insurance forms	Mostly PCOS for the foreseeable future, according to Yale Medicine
Disease classification codes (ICD)	Being taken forward with WHO as part of implementation
The International Guideline	New name to be built in at the 2028 update

If your GP or gynaecologist uses PCOS, or has not yet heard of PMOS, that is not a sign of poor care. The consensus was published in May 2026, and coding systems, textbooks and record templates take years to update, which is exactly why a transition period was planned. Using both names in the same sentence, for example "PMOS, previously called PCOS", is a simple way to avoid confusion at appointments, in referrals and when searching for information.

What to do if you already have a PCOS diagnosis

The useful changes are in what you ask for, not in what you call it.

Use both names when it helps: on forms, in searches, and when talking to a new clinician or insurer.
Ask about metabolic checks: the 2023 international guideline recommends assessing blood sugar status at diagnosis regardless of body size, then repeating it based on your individual risk. Johns Hopkins Medicine also describes checking cholesterol and triglycerides.
Mention mood and sleep: anxiety, low mood and tiredness are part of the condition, not a separate complaint to leave out.
Keep your own cycle record: dates and a few relevant symptoms make it easier to see whether a change is persistent. Our guide to PCOS cycle patterns covers what is worth recording.
Be wary of anything sold as a fix: a new name does not come with a new cure, test or supplement. Anyone promising to "reverse" PMOS is going beyond what the guidance says.

What an app can and cannot tell you

A cycle log can show how far apart your periods are, whether you have fewer than eight a year, or whether a gap has passed 90 days, which are thresholds the international guideline uses for assessment. It cannot measure androgens or AMH, see your ovaries, or tell PMOS apart from a thyroid problem, pregnancy, perimenopause or the effects of contraception. The irregular periods guide explains those overlaps.

In Flowy, the list of health conditions you can choose during onboarding currently names the condition PCOS. Choosing it records what you tell the app. It does not diagnose, confirm or rule out anything. Flowy can keep cycle dates and selected symptoms together, and the privacy page explains that it does not sell personal or health data and that you can export or reset your entries.

When cycles are irregular, any calendar estimate of ovulation or the next period is less reliable, and a period tracker is not contraception. The fertile-window guide explains why predictions cannot identify a safe day.

When to contact a healthcare professional

The NHS advises seeing a GP if you think you might have PMOS, or if symptoms are affecting your everyday life, work or relationships. It is also reasonable to book a routine appointment if your periods are more than 35 days apart, you have fewer than eight a year, or you go 90 days without one. If you are not sure how to describe the pattern, a symptom diary for your appointment can help.

Seek urgent care for very heavy bleeding with dizziness or breathlessness, or for sudden severe pelvic pain. These need assessment in their own right and should not be put down to PMOS.

Frequently asked questions

Is PMOS a different condition from PCOS?

No. PMOS is a new name for the same condition. The Lancet consensus describes it as an update to the name, not a new diagnosis.

Do I need to be re-diagnosed with PMOS?

No. The diagnostic criteria have not changed, and Yale Medicine says an existing PCOS diagnosis remains valid.

Will my medical records or insurance change?

Probably not for some time. Yale Medicine says to expect PCOS on records, prescriptions and insurance forms for the foreseeable future, and the transition is planned over three years.

Does the new name mean the ovaries are not involved?

The ovaries are still part of the condition, which is why "ovarian" stays in the name. The change reflects that the small follicles seen on ultrasound are not pathological cysts, and that hormones and metabolism matter just as much.

Why does the NHS say PMOS when my doctor says PCOS?

Public information pages can be updated quickly, while records, codes and training take longer. Both terms are correct during the transition.

The short version

PMOS is the new, more accurate name for PCOS. Your diagnosis, the criteria and the treatment options are the same, and both names will be in use until at least the 2028 guideline update. The practical gain is a clearer reason to ask for care that covers metabolism and mental health as well as periods.

This article is for general education only. It is not a diagnosis, individualised medical advice, or a substitute for care from a qualified healthcare professional.