As of the 12^th May 2026, ‘polycystic ovary syndrome’ (PCOS) no longer exits, and is officially replaced with Polyendocrine Metabolic Ovarian Syndrome, or PMOS. The change, published in The Lancet, is the result of an unprecedented 14-year global collaboration involving researchers, clinicians, and – crucially - the patients themselves.

It affects 170 million (1 in 8) women worldwide, is typically searched for 1-2 million times per month globally and is the subject of thousands of patient communities. And yet, for decades, it’s very name has been misleading, steering patients, doctors, and researchers in the wrong direction.

Why did PCOS need renaming?

“Polycystic” implies the defining feature is multiple cysts on the ovaries. It isn’t - in fact, a related study by the same researchers found no increase in abnormal ovarian cysts in the condition at all. This single mis-framing has led to decades of women being dismissed when their ultrasounds look “normal”, and clinicians focusing on the wrong organ entirely.

PMOS, by contrast, tells a more complete story. It is a condition involving the endocrine system, metabolism, and the ovaries - not as the primary site of pathology, but as one part of a multi-system picture. Women with PMOS commonly experience irregular periods, elevated androgen levels, insulin resistance, increased risk of type 2 diabetes, cardiovascular disease, and significant psychological impacts including anxiety and depression.

Polyendocrine Metabolic Ovarian Syndrome (PMOS)

Polyendocrine: Reflects the multi-hormonal, systemic nature.

Metabolic: Acknowledges insulin resistance, diabetes risk, cardiovascular impact.

Ovarian: Retained to preserve continuity — but reframed in context.

The Consensus.

The process for change involved 56 patient and professional organisations, more than 22,000 survey responses, and multiple international workshops with both patients and multidisciplinary health professionals.

The result?

“Evolutionary rebranding” - preserving some continuity with the existing name and acronym rather than a complete overhaul.

What happens next is just as significant - clinical guidelines, medical curriculum, and international disease classification systems will be updated. It needs to be more than a terminology shift - what follows should be a commitment to change - in teaching, understanding, funding, and treatment.

Will it actually change how women’s health is treated?

This the most important question, and the answer? - let’s hope so!

The optimist in me…

• A more accurate name invites a broader range of specialists like endocrinologists, cardiologists, and mental health professionals into the conversation, rather than leaving care just with gynaecology.

• Better framing tends to attract better research funding and more targeted policy attention.

• The scale of the consensus process — 56 organisations over 14 years — shows (hopefully) genuine institutional commitment, not just performative change.

• Updated classification systems mean the shift will be embedded in how doctors are trained, not just recommended.

…but still be cautious…

• Name changes in medicine have a mixed track record. The underlying problem for women’s health issues being dismissed is cultural, not terminological.

• Adoption across global healthcare systems will take years (possibly decades) and could be inconsistent.

• Some patients who have built communities and identities around the PCOS label may find the transition disorienting or overwhelming.

• Without sustained pressure from advocates and funding commitments, the rename risks becoming just symbolic.

The attention around the renaming highlights how women’s health has been historically under-researched and under-treated. Alongside growing recognition of conditions like endometriosis, perimenopause, and PMDD, this is medicine slowly — sometimes too slowly — catching up with lived experience.

Whether PMOS leads to better consultations, faster diagnoses, and more holistic care will depend on what happens next: in research funding decisions, in medical school, and in the consultation room conversation between doctor and patient - who may have been waiting for years for answers.

Teede HJ, Khomami MB, Morman R, et al. “Polyendocrine metabolic ovarian syndrome, the new name for polycystic ovary syndrome: a multistep global consensus process.” The Lancet. Published online May 12, 2026. DOI: 10.1016/S0140-6736(26)00717-8