Why changing polycystic ovary syndrome (PCOS) to polyendocrine metabolic ovarian syndrome (PMOS) matters

In May, The Lancet, a renowned peer-reviewed medical journal, put forth a change to the name of the condition formerly known as polycystic ovary syndrome (PCOS), a decision that “took 14 years of global collaboration,” according to the Endocrine Society. More than 50 organizations, including the American Society for Reproductive Medicine, contributed to the effort to rename the condition polyendocrine metabolic ovarian syndrome (PMOS). 

Professor Helena Teede, director of Monash University’s Monash Centre for Health Research and Implementation and an endocrinologist, was one of the driving forces behind the change. She reasoned that the previous term was inaccurate, as it focused on ovarian cysts while “obscuring diverse endocrine and metabolic features.” Teede believes this contributed to “delayed diagnosis, fragmented care, and stigma, while curtailing research and policy framing.” Since the condition affects roughly one in 10 women and those assigned female at birth, delayed or incorrect diagnosis could have affected millions. 

To understand the magnitude and meaning of the name change, it’s important to consider the vast history of the condition. In his treatise “Diseases of Women,” Hippocrates (460–370 B.C.) observed “those women whose menstruation is less than three days or is meagre, are robust, with a healthy complexion and a masculine appearance; yet they are not concerned about bearing children nor do they become pregnant.” This description resembled features later incorporated into diagnostic criteria. In 1884, French physician Dr. Achille Chereau wrote about ovaries “with smooth and shiny surface[s], containing many small cysts,” a description that, like many others in that time, focused on macroscopic features. 

Enter Drs. Irving Stein and Michael Leventhal, whose 1935 report titled “Amenorrhea associated with bilateral polycystic ovaries” would go on to be described as a “a remarkably lasting and influential publication,” having been thought to have led to exponential increase in related research. Stein and Leventhal coined the term “polycystic ovary syndrome,” one of several names used to describe the condition, including “polycystic ovarian syndrome,” “polycystic ovary disease” and “Stein-Leventhal syndrome.” 

In 1990, the first formal diagnostic criteria for the condition were established by the National Institutes of Health during a sponsored conference on PCOS. Individuals were required to exhibit both criteria to be diagnosed with PCOS:

1. Chronic lack of ovulation and
2. Excess androgens, or hormones which typically occur in higher quantities in males.

In addition, all other conditions with similar symptoms had to be ruled out of consideration. Though these criteria provided an important push for standardization, many began to consider that the condition affected more individuals than the criteria suggested. In 2003, new diagnostic criteria were suggested and widely implemented. This consensus, known as the Rotterdam criteria, required individuals to meet at least two out of three of the following criteria:  

1. Chronic infrequent, absent or irregular ovulation/periods, 
2. Excess androgens, or hormones which typically occur in higher quantities in males and
3. Polycystic ovaries.

Once again, physicians had to first rule out other conditions with similar symptoms such as “congenital adrenal hyperplasia, androgen-secreting tumors” and “Cushing’s syndrome.” 

According to Elle Murata, a UCSB neuroscience doctoral candidate and the Director of Science Communication at the Ann S. Bowers Women’s Brain Health Initiative, the Rotterdam criteria still had limitations, and today, the condition remains underresearched and often overlooked by physicians. 

In a 2023 TEDx Talk, Murata described her own experience with the condition, which took two years to be diagnosed. She explained that a typical timeline of diagnosis could be anywhere from “two to five years,” meaning that “it can take up to half a decade to diagnose a disorder that impacts one in 10 women.” She also outlined how her experience was one of many examples of mistreatment at the hands of medical professionals that individuals assigned female at birth often experience. Murata’s personal experience, along with her background in women’s brain health, led her to examine “how PCOS and endometriosis affect brain structure and function” at UCSB.

“Since the beginning of time, women’s pain and women’s bodies have not been taken seriously,” Murata said of her perspective on existing PCOS diagnosis practices.

These efforts, along with the name change, can lead to an increase in the general public’s understanding of the condition. Reducing the emphasis on ovarian cysts and shifting toward a broader focus on a range of metabolic, endocrine and physical symptoms through evidence-based international guidelines also could mean an increase in accurate diagnoses. Today, physicians may ask patients about their symptoms, and could recommend a pelvic exam, blood tests or an ultrasound for further testing, instead of relying solely on standard diagnostic criteria. 

The name change also reflects a wider initiative for advancing women’s health research. Correcting outdated or misleading names for conditions is an important first step in order to advocate for research on the conditions themselves; a longitudinal study of healthcare professionals and individuals with PMOS by professor Teede’s team analyzed the potential benefits of the name change, where a name change was expected to “enhance awareness, diagnosis, care quality, research coherence, and patient experience, strengthening policy, advocacy, and health outcomes globally.” 

The name change could also contribute to a broader movement to challenge outdated healthcare beliefs and increase awareness of other conditions within women’s health.

One such condition is endometriosis. According to Loughborough University medical sociology professor Dr. Nicky Hudson,  the “ambiguity” regarding endometriosis, often described as the “missed disease,” is “a result of structural, cultural and political processes and forces” that have long existed. Endometriosis, she elaborates, exemplifies “undone science,” or areas of research that are underfunded and unrecognized. Hudson asserts that endometriosis lacks research funding and government policy in comparison to other “long-term conditions such as diabetes and asthma,” which could be due to “the association of endometriosis with historically specific constructions of menstruation and women’s pain” that are outdated and harmful. 

Ultimately, the name change to PMOS could draw attention to research gaps and examples of undone science, challenge scientists to consider other inaccuracies and work towards correcting outdated constructs regarding women’s health. 

A version of this article appeared on p.11 of the Oct. 1, 2026 edition of the Daily Nexus.