PCOS gets a new name, and a more accurate one

AUSTRALIA – Monash University and an international consortium of 56 academic, clinical, and patient organisations have formally renamed polycystic ovary syndrome (PCOS) to polyendocrine metabolic ovarian syndrome (PMOS), in a Health Policy paper published in The Lancet on 12 May 2026.

PMOS affects one in eight women globally, or more than 170 million women during their reproductive years. Despite its scale, the condition has long been misunderstood, as the old name reduced a complex multisystem hormonal and metabolic disorder to an inaccurate focus on ovarian cysts.

The term PCOS implied the presence of abnormal ovarian cysts, which are not a characteristic of the condition. What appears on ultrasound are not abnormal cysts but arrested follicles, or eggs that stopped developing before they were ready, due to the syndrome's hormonal disruption.

According to the Lancet paper, this inaccuracy has contributed to delayed diagnosis, with up to 70% of affected individuals remaining undiagnosed, alongside widespread knowledge gaps, patient dissatisfaction, and limited research and policy progress.

"What we now know is that there is actually no increase in abnormal cysts on the ovary, and the diverse features of the condition were often unappreciated," said Professor Helena Teede, Director of the Monash Centre for Health Research & Implementation and an endocrinologist at Monash Health, who led the renaming effort.

The decision to use PMOS emerged from a structured, multistep process, generating more than 22,000 responses from patients and multidisciplinary health professionals across all world regions. 86 per cent of respondents supported adopting an accurate, symptom-based name over retaining the PCOS acronym or using a generic term.

For the people on the helm of this renaming effort, arriving at the final name required eliminating several strong candidates. Metabolic endocrine reproductive syndrome was ruled out because its acronym, MERS, duplicates that of Middle East respiratory syndrome.

Another name candidate, Endocrine Metabolic Ovulatory Syndrome, which initially ranked highest, was dropped after it was found to overlap with the "emo" youth subculture label, a cultural association the team judged harmful to the condition's credibility. 

Cultural appropriateness was also a significant factor in the process. The term reproductive was initially considered but dropped due to its potential to heighten stigma in cultures where fertility is closely tied to a woman's perceived worth, a concern with direct relevance to Singapore and the broader Southeast Asian context.

"It was essential that the new name was scientifically correct but also considered across diverse cultural contexts," said Professor Terhi Piltonen, President of the AE-PCOS Society and international co-lead from Oulu University Hospital, Finland.

A three-year global transition period is now under way, supported by a major international education and awareness campaign reaching those affected, health professionals, governments and researchers around the world, with the new name to be fully implemented in the 2028 International Guideline update.