For more than two decades, I have studied a condition that shapes the lives of about 10-13% of women. This condition causes complex, wide-ranging symptoms such as irregular periods, excessive hair growth, weight gain, acne and difficulty getting pregnant.
Until a few days ago, I called it polycystic ovary syndrome, or PCOS. But from now on, I – along with my colleagues, doctors and patients – will call it something different: polyendocrine metabolic ovarian syndrome, or PMOS.
The renaming was announced in a consensus paper just published in The Lancet. It is the result of a process that has taken over ten years, involved more than 22,000 people across six continents, and brought together 56 patients and professional organisations.
Some readers will see “PMOS” and wonder why scientists have spent so much energy on changing just three letters. As one of the researchers involved, I want to explain why this small change is, in fact, a very big one – and why we hope it will lead to better care for patients.
A name that didn’t fit
The old name was a historical accident.
When the doctors who first studied the condition examined affected ovaries under the microscope – and later by ultrasound – they saw clusters of small, fluid-filled sacs they thought were cysts. So the label “polycystic” stuck.
But those structures are not actually cysts. They’re immature egg follicles that have stalled at an early stage of development. Crucially, many people who are diagnosed with PCOS (now PMOS) do not even exhibit these abnormalities in their ovaries.
The name “PCOS” focused attention on a part of the body that, for many patients, is the least of their problems. And it implied the condition was solely a gynaecological issue. In reality, it’s a complex hormonal and metabolic disorder that begins early in life and lasts a lifetime.
Decades of research, including work done in my laboratory at Karolinska Institutet, has shown that the condition involves a range of interacting disturbances.
Levels of male hormones (androgens) are often elevated in those with the condition. The brain’s signalling to the ovaries is altered. The body’s response to insulin is blunted as well, which is why people with the condition have higher rates of type 2 diabetes, obesity, fatty liver and cardiovascular disease. There is also an increased risk of depression, anxiety, sleep apnoea and endometrial cancer.
That is why the new name has three parts.
“Polyendocrine” reflects the multiple hormonal systems involved. “Metabolic” recognises the lifelong risk of diabetes and heart disease. “Ovarian” maintains the link to ovulation problems and infertility, which remain core features.
The consensus process behind the change was unusually rigorous. Patients and doctors from every world region were surveyed in successive rounds, with their answers shaping the options offered in the next round’s survey. More than 14,000 people, over half of them living with the condition themselves, voted on candidate names. The final agreement was reached in February this year.
Why a name matters for care
A name is not just a name. It tells doctors where to look, tells researchers what to study, and tells people with PMOS what to expect.
Under the old label, many women were told their symptoms were a fertility issue or a weight issue. Diagnosis took, on average, more than two years – and up to 70% of patients reported initially being dismissed or misdiagnosed before finally getting a diagnosis.
Few were warned about their lifelong increased risk of metabolic disease. In many parts of the world, care was fragmented among gynaecologists, endocrinologists, dermatologists and mental-health professionals, with no one taking responsibility for the whole patient.
With PMOS, the multi-system nature of the condition is now recognised in the name. I hope this means general practitioners will check insulin, blood sugar, blood pressure and mental wellbeing when examining and diagnosing patients – not only looking at their menstrual periods.
I hope as well that the condition’s name change means teenage girls, who often show the earliest signs, will be identified and supported sooner. And that researchers find it easier to secure funding to study the metabolic, cardiovascular and neurological aspects of the disorder.
The name change may also empower women living with PMOS in seeking a diagnosis or treatment.
The diagnostic criteria for PMOS remain the same. If you already have a PCOS diagnosis, it will now be referred to as PMOS. You won’t need to undergo any new tests or attend new appointments.
The transition will be phased in over the next three years through updated clinical guidelines, medical education and international disease-coding systems.
We have not solved this condition. There is still no cure, and the first-line treatment is still lifestyle change – supported when needed by medications such as hormonal contraceptives, metformin (which can help control blood sugar) and, more recently, GLP-1 receptor agonists (which can help with managing blood sugar and may also lead to weight loss).
But getting the name right is the foundation that everything else rests on. After almost a century of mislabelling, we finally have a name that matches the science. I hope this name that will help the 170 million women living with this condition get the care they have always deserved.
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Elisabet Stener-Victorin receives funding from Novo Nordisk Foundation, Swedish Research Council, and Diabetes Foundation.