PCOS is now called PMOS

If you were diagnosed with polycystic ovary syndrome, the condition you have now has a different name.

On 12 May 2026, The Lancet published the outcome of a global consensus process renaming it Polyendocrine Metabolic Ovarian Syndrome, or PMOS (Teede et al., 2026).

It is less a rebrand and more a correction. Part of the old name was inaccurate, and the rest of it was too narrow.

The problem with the old name

The cysts in "polycystic" are not cysts.

What shows on an ultrasound in many women with the condition is a number of small follicles, which are ordinary structures the ovary produces. Professor Helena Teede, the paper's first author, put it plainly in the announcement: "What we now know is that there is actually no increase in abnormal cysts on the ovary."

A woman can be diagnosed with the condition and have entirely typical-looking ovaries. Ovarian appearance is one possible criterion among several, and a diagnosis can be made without it.

So the name pointed at a feature that is often absent, sometimes irrelevant, and misnamed even when present.

What that name cost

The Endocrine Society, one of the 56 organisations behind the change, described the old name as reducing "a complex, long-term hormonal or endocrine disorder to a misunderstanding about 'cysts' and a focus on ovaries," and stated that this "contributed to missed diagnoses and inadequate treatment."

The consensus paper gives five reasons for rejecting the old name.

It centres ovarian cysts, which are not required for diagnosis. It names one organ when the condition affects several. It delays diagnosis and gets in the way of communication between patients and doctors. It complicates research and health system coding.

And one more, which lands hardest here. The reproductive focus of the name can reinforce stigma, particularly in places where fertility carries high social value. Many people report distress at the name itself.

The delay is the one worth sitting with. A name tells a doctor where to look. This one pointed at the ovaries while the condition was working across the hormonal and metabolic systems, and women waited years for an answer as a result.

That is where the widely-quoted "70% undiagnosed" figure comes from: one Australian community, not a worldwide count. No equivalent Indian study exists yet.

What the new name says instead

Read the three words separately.

Polyendocrine. More than one hormone system is involved. Not one gland, not one hormone, and not only the reproductive ones.

Metabolic. How the body handles energy, insulin and fat storage sits inside the condition itself. A gold-standard clamp study found insulin resistance in 85% of the women with the condition it tested, and in 75% of those in the lean BMI range (Stepto et al., 2013). That was 40 women in one Australian study, so treat it as a strong signal rather than a settled number. A later meta-analysis of clamp studies found the same in women across Australia, Europe and North America (Cassar et al., 2016). Insulin resistance in PMOS is not a consequence of weight. Carrying more weight adds to it rather than causing it. Which specialist handles the metabolic side is not always obvious, which is why we wrote a guide on which doctor to see for hormonal symptoms.

Ovarian. The ovaries are still involved. They are one part of a larger picture.

The new name describes a hormonal and metabolic condition that involves the ovaries. The old one described an ovarian condition. That difference is the entire point.

How the decision was made

This matters as much as the name itself, because the obvious question about any renaming is who decided.

The final round of surveys drew 14,360 responses, 10,411 from people with PCOS and 3,949 from health professionals, building on 7,708 responses gathered in earlier rounds. Alongside the surveys ran a series of international workshops using structured consensus methods. Fifty-six academic, clinical and patient organisations took part, including the Endocrine Society, the European Society of Human Reproduction and Embryology, and the Androgen Excess and PCOS Society. The result was published in The Lancet, which is about as high as the bar goes in medical publishing.

What happens now

There is a three-year transition period. Full implementation lands with the 2028 update to the International Evidence-Based Guideline.

Practically, that means both names will be in use for a while. Your medical records, your doctor, your test requisitions and most of the internet will say PCOS for some time yet. Both names are correct during the transition.

If you have an appointment coming up, it is worth taking a list of questions in with you. For a condition you have already been diagnosed with, our follow-up appointment questions cover what to settle before you leave.

Why this lands differently in India

PMOS is more prevalent among Indian women than the global average.

The largest Indian study so far comes from the ICMR PCOS National Task Force. It covered eight states and 8,993 women aged 18 to 40, and found a prevalence of 19.6% under Rotterdam criteria, close to one in five (Ganie et al., 2024, JAMA Network Open). Globally the figure is around one in eight, or more than 170 million people (Neven et al., 2026, Human Reproduction Update). That same analysis puts the WHO South-East Asia region, which includes India, at around 14%. That is the second highest of any region. But the range is wide, 5.8% to 25.9%, and there is no separate figure for India.

There is a second reason the rename matters here specifically.

Indian clinical practice already recognises that metabolic thresholds differ for Indian bodies. Obesity is defined at a BMI of 25 rather than 30, because the metabolic risk arrives at a lower weight. Applied to the same group of apparently healthy Indian women aged 18 to 40, the WHO threshold puts 8.1% in the obese range and the Indian threshold puts around 40% (Ganie et al., 2023, JMIR Public Health and Surveillance). Same women, two standards, two very different answers.

The new name puts metabolism in the title. That matches what the Indian data shows.

We use PMOS across this site, with "PMOS (formerly PCOS)" on first mention for as long as the transition runs, since PCOS is still the term most people search for.