Polycystic ovary syndrome, long known as PCOS, is officially being renamed polyendocrine metabolic ovarian syndrome (PMOS) to better reflect the full scope of the condition and its impact beyond the ovaries. We sat down with Megan Evans, MD, MPH, an Obstetrician and Gynecologist at Tufts Medical Center and Associate Professor, Tufts University School of Medicine, to answer some of the biggest questions patients are asking about the transition from PCOS to PMOS.
Why is PCOS being renamed to PMOS?
The name "polycystic ovary syndrome" has long been recognized as inaccurate and misleading, even by the medical community. It suggests the condition is mainly about ovarian cysts, when in reality it involves multiple hormone systems, metabolism and affects the whole body. Up to 70% of people with this condition remain undiagnosed, and confusion around the name is part of the problem. After years of advocacy from patients and clinicians, a global effort was launched to find a name that actually reflects what the condition is.
What is PMOS?
Polyendocrine metabolic ovarian syndrome (PMOS) is the new name for what was previously called PCOS. It's the same condition, affecting roughly 1 in 8 women worldwide, but with a name that more accurately captures its true nature: multiple hormonal and metabolic disturbances, along with ovarian dysfunction. Nothing about how the condition behaves has changed, only how we refer to it.
Why was the term "polycystic ovary syndrome" considered inaccurate?
The word "polycystic" implies the presence of pathological ovarian cysts, but actual cysts are not a feature of this condition. What's seen on ultrasound is an accumulation of small follicles, which is very different. The old name only focused on the ovaries, completely missing the broader hormonal and metabolic picture. For many patients, hearing "cysts" caused unnecessary fear, and the narrow framing led some doctors (and insurers and policymakers) to underestimate the condition's true complexity and impact.
How does PMOS better reflect the condition?
Each word in the new name earns its place. Polyendocrine reflects that multiple hormone systems are involved, including insulin, androgens and reproductive hormones. Metabolic acknowledges the very real risks of insulin resistance, type 2 diabetes and cardiovascular disease that come with the condition. Ovarian captures the follicular and hormonal dysfunction in the ovaries without the misleading implication of cysts. Together, the name tells a much more complete and accurate story.
Is PMOS more focused on metabolic health and insulin resistance?
Yes, and appropriately so. The published paper highlights that insulin resistance affects approximately 85% of people with this condition, including about 75% of those who are lean. This metabolic dimension has often been underappreciated or undertreated. By building "metabolic" directly into the name, the hope is that clinicians, researchers and patients will all give this aspect the attention it deserves from the start.
Does the PMOS name change affect diagnosis or treatment?
No. The diagnostic criteria haven't changed. Diagnosis is still based on the same criteria used today: irregular ovulation, signs of elevated androgens and ovarian findings on ultrasound or anti-Müllerian hormone (AMH) levels—a hormone produced by the small follicles in the ovaries. Treatment approaches are also unchanged. Think of this as correcting the label on a bottle whose contents you already know well. The medicine inside is the same.
What does the change mean for future research and advocacy?
Potentially, a great deal. A more accurate name could help better align research funding, policy attention and disease classification systems—including the World Health Organization's ICD (International Classification of Diseases) coding system, which standardizes diagnoses, symptoms and injuries into universal alphanumeric codes—with the true scope of the condition. When a condition sounds like a niche gynecological issue, it often receives niche-level attention and resources. PMOS better reflects that this is a serious, multisystem condition affecting an estimated 170 million women worldwide, creating a stronger foundation for advocacy, awareness and research investment.
How could the name change improve patient care and awareness?
In several important ways. A clearer name can prompt earlier and more accurate diagnosis. It may help patients advocate for comprehensive care, not just reproductive management, but metabolic monitoring and psychological support too. It also reduces stigma, particularly the distress many patients felt being told they had "cysts" on their ovaries, or feeling reduced to a fertility diagnosis. Patients who feel accurately seen and understood tend to have better experiences and outcomes.
What should current PCOS patients know about the transition to PMOS?
First and most importantly, you have the same condition and your care doesn't change. The transition is planned to happen gradually over three years, so you will likely hear both terms for a while. The renaming was driven in large part by patient advocates, and people with PCOS were involved at every stage of the process, from designing the surveys to co-leading the workshops. This change was done with patients, not just for them.
Will doctors continue using the term PCOS during the transition period?
Yes, likely for some time. The paper explicitly calls for an evolutionary approach rather than an abrupt switch, meaning the transition will be gradual and supported. The new name will be integrated into electronic health records, clinical guidelines and the WHO disease classification system over the next few years, with a key milestone being the 2028 update to the International Guidelines. In the meantime, both terms will circulate, and that's by design. The goal is continuity, not confusion.
If you think you may have PCOS/PMOS, or haven't gotten clear answers about your symptoms, our OBGYN specialists are here to help.
