PMOS

Introduction: A Historic Name Change

PMOS—Polyendocrine Metabolic Ovarian Syndrome—is the new name for a condition previously known as Polycystic Ovary Syndrome (PCOS). This change, announced in May 2026 after a 14-year global consensus process, represents a major shift in how this condition is understood and treated.

The renaming effort was led by Monash University Professor Helena Teede and involved more than 22,000 patient survey responses, 56 patient and professional organisations, and collaboration with experts from around the world. The new name better reflects that this is a complex, lifelong hormonal and metabolic condition affecting multiple body systems—not just the ovaries.

PMOS affects approximately 1 in 8 women of reproductive age—more than 170 million people worldwide. Yet up to 70% of affected women remain undiagnosed, partly due to misconceptions created by the old name.

What Is PMOS?

PMOS is a chronic condition characterised by disruptions in hormones and chemical messengers in the body. It affects metabolic health, mental health, skin, and the reproductive system.

Importantly, PMOS is not a disease of ovarian cysts. The “cysts” referenced in the old name are actually immature follicles—tiny, fluid-filled sacs that contain eggs. In PMOS, disrupted hormonal signals cause these follicles to stall instead of maturing and releasing an egg.

Key features of PMOS include:

Endocrine changes affecting hormone balance
Metabolic dysfunction, particularly insulin resistance
Systemic effects across multiple body systems
Highly variable presentation from person to person

Why the Name Changed from PCOS to PMOS

The old name, “Polycystic Ovary Syndrome,” was widely recognised as misleading and reductive. It placed undue focus on the ovaries while ignoring the broader metabolic and endocrine features of the condition.

Problems with the Old Name

Inaccurate focus on cysts: Research shows there is no increase in abnormal ovarian cysts in women with PMOS. The term “polycystic” created confusion with pathological ovarian cysts.
Missed diagnoses: The old name contributed to delayed diagnosis, limited awareness, and inadequate care.
Ignored metabolic aspects: Insulin resistance affects 75-95% of women with PMOS—even those with a healthy weight. The old name did not capture this critical dimension.
Reduced to reproductive health: The name PCOS implied the condition was primarily gynaecological, overlooking the lifelong metabolic and cardiovascular risks.

What the New Name Represents

The new name was chosen based on several key principles: patient benefit, scientific accuracy, ease of communication, avoidance of stigma, cultural appropriateness, and accompanying implementation support.

Polyendocrine: Reflects the hormonal system involvement across multiple endocrine organs
Metabolic: Acknowledges the central role of metabolic dysfunction, especially insulin resistance
Ovarian: Recognises that ovaries are involved but not the sole focus
Syndrome: Highlights that this is a complex of features rather than a single disease

The name change is being implemented over a three-year transition period, with full adoption expected in the 2028 International Guideline update.

Common Symptoms of PMOS

PMOS shows up differently in each person. Some experience only mild hormonal changes, while others struggle with multiple overlapping issues.

Reproductive and Hormonal Symptoms

Irregular or missed periods (cycles shorter than 22 days or longer than 34-35 days)
Difficulty getting pregnant due to infrequent ovulation
Excessive facial or body hair growth (hirsutism)
Thinning scalp hair
Acne on the face, chest, or back

Metabolic Symptoms

Weight gain, especially around the abdomen
Difficulty losing weight
Feeling very tired
Darkened, velvety skin in body folds (acanthosis nigricans)—a sign of insulin resistance

Psychological Symptoms

Depression and anxiety (significantly higher rates than the general population)

Important Note

Not everyone with PMOS has all these symptoms. “Not everyone with PMOS struggles with their weight or infertility. And not every woman with PMOS has irregular periods,” explains Dr Jessica Chan, a reproductive endocrinologist at Cedars-Sinai.

How PMOS Is Diagnosed

There is no single test for PMOS. Diagnosis involves a combination of clinical evaluation, blood tests, and sometimes ultrasound.

Diagnostic Criteria for Adults

Following the updated 2023 International Guideline, a PMOS diagnosis requires two of the following three criteria:

Oligo- or anovulation: Irregular or absent menstrual cycles
Clinical and/or biochemical hyperandrogenism: Signs of excess male hormones (e.g., hirsutism, acne) or elevated testosterone on blood tests
Polycystic ovary morphology or elevated AMH: On ultrasound (for adults) OR elevated anti-Müllerian hormone (AMH) levels

Doctors must also exclude other conditions that can cause similar symptoms, including thyroid disease, Cushing syndrome, and adrenal disorders.

Diagnosis in Adolescents

Diagnosing PMOS in adolescents is more complicated because puberty changes—such as menstrual irregularity and hormonal fluctuations—can mimic PMOS features.

For adolescents, both of the following must be present:

Abnormal uterine bleeding pattern (persisting for 1-2 years)
Evidence of hyperandrogenism (elevated testosterone, moderate to severe hirsutism, or moderate to severe inflammatory acne)

Ultrasound is generally not recommended for diagnosing PMOS in adolescent girls, as polycystic ovary morphology is found in less than 40% of girls and does not predict the presence or development of PMOS.

Common Diagnostic Tests

Test	Purpose
Blood tests	Check hormone levels (testosterone, AMH), screen for insulin resistance, and rule out other conditions
Pelvic ultrasound	Examine ovaries for multiple follicles (adults only)
Metabolic screening	Assess blood sugar, cholesterol, and cardiovascular risk factors
17-hydroxyprogesterone	Screen for nonclassic congenital adrenal hyperplasia in adolescents

Health Risks Associated with PMOS

PMOS is associated with several long-term health risks that extend well beyond the reproductive years.

Metabolic Risks

Type 2 diabetes: Insulin resistance is a core feature of PMOS
Dyslipidaemia: Abnormal cholesterol and lipid levels
Hypertension: Increased risk of high blood pressure

Cardiovascular Risks

Research has shown increased risk of:

Major adverse cardiovascular events
Myocardial infarction (heart attack)
Angina
Need for revascularisation

Importantly, these cardiovascular risks are not simply due to obesity—studies of Nordic women with PMOS confirmed that even those with a BMI under 25 kg/m² had elevated cardiovascular risk.

Gynaecological Risks

Endometrial hyperplasia: Thickening of the uterine lining due to unopposed oestrogen
Increased risk of endometrial cancer: If the lining becomes too thick

Psychological Risks

Significantly higher rates of depression and anxiety compared to the general population

The condition does not disappear after menopause—metabolic features tend to predominate in later life, meaning ongoing monitoring and management are essential.

Treatment Options for PMOS

There is currently no cure for PMOS, and no FDA-approved treatments specifically for the condition. However, effective strategies are available to manage symptoms and reduce long-term risks.

Hormonal Medications

Estrogen-progestin contraceptives are often first-line treatment for managing irregular periods, acne, and hirsutism. These medications:

Cause regular shedding of the endometrium
Reduce the risk of endometrial hyperplasia and cancer
Decrease circulating androgens, improving acne and hirsutism

Other hormonal options include:

Cyclic oral progestins (e.g., medroxyprogesterone)
Levonorgestrel intrauterine device (IUS)
Antiandrogenic progestins (drospirenone, dienogest)

Medications for Insulin Resistance

Metformin (500-1000 mg twice daily) can help improve insulin sensitivity when lifestyle modifications are insufficient. Benefits include:

Making menstrual cycles more regular
Reducing free testosterone levels
Correcting metabolic and glycaemic abnormalities

However, metformin has little or no effect on hirsutism, acne, or infertility.

GLP-1 weight loss medications that target insulin pathways may also help alleviate symptoms.

Fertility Treatments

For women trying to conceive:

Letrozole or clomiphene: Medications to stimulate egg release
Laparoscopic ovarian drilling: A surgical procedure using heat or laser to remove ovarian tissue, which may help release more eggs
Metformin: May induce ovulation, so contraception is important if pregnancy is not desired

Medications for Specific Symptoms

Spironolactone or eflornithine: To reduce excess facial and body hair
Skin creams or tablets: For acne management

Living with PMOS: Lifestyle Changes That Help

Lifestyle modifications are a cornerstone of PMOS management, particularly for addressing insulin resistance and metabolic features.

Weight Management

If obesity is present, weight loss and regular exercise are strongly encouraged. Benefits include:

Inducing ovulation (making cycles more regular)
Improving fertility
Increasing insulin sensitivity
Reducing hirsutism and acanthosis nigricans

However, weight loss is unlikely to benefit women with PMOS who do not have obesity—highlighting the importance of individualised care.

Diet and Exercise

Eat a healthy, balanced diet
Exercise regularly—but avoid high-intensity exercise, which can make PMOS symptoms worse
Aim for moderate, consistent physical activity

Mental Health Support

Consider talking therapy if symptoms are causing depression or anxiety
Seek support from peer networks and patient organisations

Hair Removal Options

Shaving, waxing, or hair removal creams
Permanent options: electrolysis or laser treatments

NHS Resources

In the UK, the NHS Better Health programme offers free tools and support for weight loss and physical activity.

Looking Ahead

The renaming of PCOS to PMOS is a landmark moment for women’s health. It represents a shift toward more accurate scientific understanding, better patient education, and improved healthcare delivery.

Key Takeaways

PMOS is a systemic condition—not just an ovarian disorder
Insulin resistance is present in up to 95% of affected women
Lifelong management is needed, as risks persist beyond menopause
Individualised care is essential—symptoms and responses to treatment vary greatly

What Comes Next

The new name will be fully implemented in the 2028 International Guideline update
A major international education campaign is underway to reach health professionals, governments, and communities
Health systems are updating electronic records and coding nomenclature

“This is about accountability and progress,” says Lorna Berry, an Australian woman with PMOS who played a key role in the renaming process. “It is about my daughters, their daughters, and the countless women yet to be born. We deserve clarity, understanding, and equitable healthcare from the very beginning”.

This article is for informational purposes only and does not constitute medical advice. If you think you may have PMOS, consult a healthcare professional for proper evaluation and care.

Dr Nidaa Khan

PCOS Has a New Name