Allison Sayre, MSN, WHNP
If you've recently heard the term PMOS and wondered whether it is different from PCOS, the answer is both yes and no. The condition itself has not changed, but the science behind it has.
In 2026, an international consortium of researchers, clinicians, patient advocacy organizations, and thousands of women from around the world officially recommended changing the name polycystic ovary syndrome (PCOS) to polyendocrine metabolic ovarian syndrome (PMOS). [1]
This landmark decision reflects decades of research demonstrating that the condition has always been much more than an ovarian disorder. While reproductive symptoms remain an important feature, PMOS is increasingly recognized as a complex endocrine and metabolic condition that can influence hormone balance, fertility, insulin sensitivity, cardiovascular health, mental well-being, and quality of life. [1][2]
The new name represents an important step toward improving awareness, reducing stigma, encouraging earlier diagnosis, and helping women better understand what is actually happening inside their bodies.
Why Did PCOS Become PMOS?
The original name, polycystic ovary syndrome, unintentionally created confusion. Many women diagnosed with PCOS never develop ovarian cysts. Instead, imaging may reveal multiple small, immature follicles that have stopped developing normally. These are not pathological ovarian cysts, making the original terminology scientifically inaccurate. [1][2]
The name also focused almost entirely on one organ while overlooking the broader hormonal and metabolic disruptions that define the condition. After an extensive international consensus process involving more than 14,000 patients and healthcare professionals, experts agreed that a new name better reflects today's understanding of the disease. [1]
Each component of polyendocrine metabolic ovarian syndrome was chosen deliberately.
- Polyendocrine recognizes that multiple hormone systems are involved, including insulin, androgens, ovarian hormones, and neuroendocrine signaling.
- Metabolic acknowledges the strong relationship between PMOS and insulin resistance, blood sugar regulation, obesity, dyslipidemia, fatty liver disease, and cardiovascular risk.
- Ovarian preserves recognition of the reproductive manifestations, including ovulatory dysfunction and infertility. [1]
The result is a name that better captures the complexity of the condition while moving away from a misleading emphasis on ovarian "cysts."
What Is PMOS?
PMOS is one of the most common endocrine disorders affecting women, impacting approximately one in eight worldwide, but despite its prevalence, it remains significantly underdiagnosed. Experts estimate that as many as 70% of affected individuals have not yet been diagnosed, often because symptoms develop gradually and vary widely between individuals. [1]
Some women primarily experience irregular menstrual cycles. Others struggle with acne, unwanted facial or body hair, scalp hair thinning, infertility, weight gain, or difficulty maintaining healthy blood sugar.
Some have relatively mild reproductive symptoms while metabolic abnormalities quietly progress for years. This remarkable variability is one reason PMOS has historically been difficult to recognize.
PMOS Is a Whole-Body Hormonal Disorder
One of the biggest shifts in our understanding of PMOS is recognizing that it is not simply an ovarian condition. Instead, it represents a network of communication changes between the brain, ovaries, pancreas, liver, and other metabolic tissues. [2]
Researchers now describe PMOS as the result of complex interactions between genetics, environmental influences, metabolism, neuroendocrine signaling, and ovarian function. [2] Rather than one hormone becoming abnormal, several hormonal systems begin influencing one another through interconnected feedback loops.
Understanding this systems biology helps explain why women with PMOS often experience symptoms affecting multiple aspects of health instead of only menstrual irregularities.
The Central Role of Insulin
One of the defining biological features of PMOS is insulin resistance. Up to 70% of women with PMOS develop some degree of insulin resistance, although severity varies considerably. [2]
When insulin levels remain elevated over time, several hormonal changes begin to occur. Higher insulin decreases production of sex hormone-binding globulin (SHBG) in the liver, allowing more free testosterone to circulate. Insulin also directly stimulates ovarian theca cells to produce additional androgens while interfering with normal follicle maturation and ovulation. [2]
This creates a self-reinforcing cycle where elevated insulin contributes to androgen excess, and androgen excess further disrupts ovarian function. Obesity frequently worsens insulin resistance, but researchers emphasize an important point. Not every woman with PMOS has obesity.
Likewise, not every woman with insulin resistance develops PMOS. The condition exists along a spectrum, reflecting different combinations of genetic susceptibility, metabolic health, and hormonal regulation. [2]
Beyond Reproductive Health
PMOS can influence far more than fertility. Women with PMOS may experience reproductive, metabolic, psychological, and dermatological manifestations. [1][2]
Reproductive features may include:
- Irregular or absent ovulation
- Irregular menstrual cycles
- Infertility
- Pregnancy complications
Hormonal manifestations may include:
- Elevated testosterone
- Acne
- Excess facial or body hair
- Scalp hair thinning
Metabolic features may include:
- Insulin resistance
- Prediabetes or type 2 diabetes
- Dyslipidemia
- Hypertension
- Metabolic dysfunction-associated steatotic liver disease
- Increased cardiovascular risk [1]
There also tends to be higher rates of anxiety, depression, eating disorders, and reduced quality of life among women living with PMOS. [1][2] Taken together, these findings reinforce why the new terminology better reflects the broad clinical impact of the condition.
How Is PMOS Diagnosed?
Although the name has changed, the diagnostic criteria remain the same.
According to current international guidelines, adults are diagnosed when at least two of the following are present after excluding other hormonal disorders [1][2]:
- Ovulatory dysfunction
- Clinical or biochemical hyperandrogenism
- Polycystic ovarian morphology on ultrasound or elevated anti-Müllerian hormone (AMH) when appropriate
Importantly, pathological ovarian cysts are not required for diagnosis. This again highlights why the previous name no longer aligned with modern scientific understanding. [1][2]
What Does the Name Change Mean for Patients?
Changing from PCOS to PMOS is about much more than terminology. Names influence how diseases are understood. They shape research priorities, medical education, healthcare policy, and public awareness.
Perhaps most importantly, they shape how patients understand themselves. By recognizing PMOS as a multisystem endocrine and metabolic condition, clinicians are encouraged to look beyond reproductive symptoms and evaluate broader aspects of long-term health, including metabolic risk, cardiovascular health, and emotional well-being. [1]
This broader perspective also supports more individualized care because every woman experiences PMOS differently.
Looking Toward the Future
The story of PMOS continues to evolve. Researchers are actively exploring the genetic architecture, neuroendocrine pathways, insulin signaling, inflammatory mechanisms, and environmental influences that contribute to the condition. [2] Each new discovery is bringing medicine closer to more personalized approaches for diagnosis, risk assessment, and treatment.
Perhaps the most encouraging aspect of the name change is what it represents. It reflects a willingness to let scientific understanding evolve. It acknowledges the lived experiences of millions of women who have long recognized that this condition affects much more than their ovaries.
Most importantly, it sends a powerful message that PMOS is increasingly being understood as a complex but manageable condition. Earlier recognition, individualized care, and growing scientific knowledge continue to improve the outlook for women living with PMOS. While the diagnosis may feel overwhelming at first, today's understanding offers more clarity than ever before and far more reasons for optimism than in years past.
The information provided is for educational purposes only. Consult your physician or healthcare practitioner if you have specific questions before instituting any changes in your daily lifestyle including changes in diet, exercise, and supplement use.
Allison Sayre, MSN, WHNP is a board-certified women’s health nurse practitioner with advanced expertise in hormonal health, integrative gynecology, and patient-centered care across the lifespan. She holds a Master of Science in Nursing and has served as both a clinical provider and educator in functional and conventional women’s health settings. At ARG, Allison contributes to medical education, clinical protocol development, and strategic content that supports the evolving needs of women's healthcare practitioners.
