Cory Ruth, a registered dietitian and women’s health expert, first started noticing irregular periods in her teens.
“I remember always feeling like something was off. In high school, we learned that you get a period every 28 days and that’s that,” she says. “That was never the case for me.”
However, Ruth wasn’t sure what exactly was wrong.
As Ruth got older and decided to become a dietitian, another student in one of her classes was discussing polycystic ovary syndrome (PCOS), which has since been renamed polyendocrine metabolic ovarian syndrome (PMOS), a condition that affects the endocrine, reproductive and metabolic systems. One of its hallmark signs? Unpredictable or irregular periods.
The symptoms seemed familiar to Ruth, and by the time she was in her mid-20s, she was diagnosed with PMOS by her OB-GYN.
PMOS is a chronic condition with life-long symptoms that can be serious, in both a physical and emotional sense. There is no cure for PMOS, nor is the cause of the condition clear, but treatments do exist to help individuals manage their PMOS symptoms and improve both their health and quality of life.
[READ: Signs of a Hormonal Imbalance.]
What Is PMOS (Polyendocrine Metabolic Ovarian Syndrome)?
PMOS is a common condition that is characterized by multiple small follicles in the ovaries, high levels of male hormones called androgens and irregular menstrual cycles. PMOS impacts the endocrine, reproductive and metabolic systems and affects up to 13% of women of reproductive age.
However, despite being fairly common, the World Health Organization estimates that up to 70% of affected people remain undiagnosed worldwide and many struggle with diagnosis.
In the female reproductive system, ovaries contain ovarian follicles, which are little sacs filled with fluid containing premature eggs. These eggs mature and are released during menstruation.
However, for some people, large amounts of follicles grow on the outside of the ovaries and cause them to become polycystic. Ovarian follicles may also fail to develop and release eggs properly, resulting in irregular periods. PMOS can also cause elevated androgens that can result in symptoms like acne or excess body hair. These conditions characterize the hormonal imbalance known as PMOS.
Why was PCOS renamed to PMOS?
An international coalition of medical experts announced in May 2026 that polycystic ovary syndrome would be renamed polyendocrine metabolic ovarian syndrome, or PMOS, marking the first official name change for the condition since it was discovered. The decision followed an extensive global consensus process involving researchers, clinicians and patient advocacy groups, who concluded that the term PCOS inaccurately emphasized ovarian cysts — a feature that isn’t universal or central to the syndrome. Experts say the new name better reflects the condition’s complex nature as a multisystem disorder involving hormonal, metabolic and reproductive dysfunction.
The old name often delayed diagnosis because patients without ovarian cysts were dismissed. The new name clearly signals that multiple hormones and metabolic functions are involved. In addition, providers are now prompted to monitor consumers for whole-body health, including insulin resistance, cardiovascular risks, high cholesterol and mental health challenges.
Does the name change affect my diagnosis or treatment?
Despite the name change, the diagnostic criteria and treatment of PMOS remain unchanged. Experts and supporters believe the PMOS designation will improve the public’s understanding of the syndrome, reduce stigma and encourage healthcare providers to recognize the broader endocrine and metabolic health risks associated with the syndrome.
[READ: Ovulation: Symptoms and Calculating When It Happens]
What Causes PMOS?
What exactly causes PMOS remains unknown. Rather than being a single disease with one cause, PMOS most likely has a variety of causes.
“It’s probably many different causes that result in similar symptoms — irregular menstrual cycles, excess androgens and polycystic ovaries,” says Dr. Hugh Taylor, chair of the Department of Obstetrics, Gynecology and Reproductive Medicine at Yale School of Medicine.
A few contributing risk factors that may be involved in PMOS are:
— Genetics. PMOS appears to have some kind of genetic element to it as it often runs in families.
— Inflammation. Chronic inflammation has been linked to PMOS in research. “We think inflammation plays a role and it may irritate the ovaries. It’s less well-defined, but in women with PMOS we do see low-grade inflammation,” says Taylor.
— Environmental factors. How environmental factors play into PMOS is less well understood, but androgen exposure in early life or as a fetus may increase the chances of someone developing PMOS.
The role of insulin resistance
It’s a common misbelief that obesity causes PMOS. While research reports that the majority of people with PMOS are either overweight or obese, obesity is not a cause of PMOS.
PMOS itself contributes to weight gain through insulin resistance and high androgen levels.
“Having PMOS does make you more prone to gain weight. For many people, gaining weight can exacerbate symptoms,” Taylor says.
It is also a common misconception that only people who have overweight or obesity have PMOS. Those who fall under the category of being a healthy weight or even underweight can still — and do — have PMOS.
“There are lots of people who are thin who have PMOS, and that is because it’s something that’s inherent to the ovaries,” says Dr. Chandra C. Shenoy, a gynecologist and reproductive endocrinologist at the Mayo Clinic in Rochester.
Genetics and hormonal imbalance
Genetics is also believed to play a significant role in the development on PMOS. Studies have shown that the condition often runs in families, suggesting that inherited genetic factors can increase your susceptibility. Researchers have identified multiple genes linked to hormone regulation, insulin signaling and ovarian function that may contribute to the syndrome. However, no single gene causes PMOS; rather, it appears to result from numerous genetic variants combined with environmental and lifestyle factors.
Hormonal imbalances are a hallmark of PMOS. Many individuals with the condition produce higher-than-normal levels of androgens,, which can lead to irregular menstrual cycles, acne and excess hair growth. Insulin resistance is also common, causing the body to produce more insulin, which can stimulate increased androgen production. These connected hormonal disruptions can affect ovulation, metabolism and make PMOS a complex endocrine disorder.
What are the four types of PMOS?
Although there are not specific medical categories of PMOS, the four most commonly proposed types of PMOS are:
1. Insulin-resistant PMOS. This type refers to PMOS that involves insulin resistance as a main component. With insulin resistance, the body’s cells don’t react to insulin the way they normally should. Instead of sugar being converted into energy, the ability to regulate blood sugar is impaired. According to research studies, 65% to 70% of women with PMOS are insulin-resistant. This type is associated with weight gain, high blood pressure and symptoms that worsen or improve depending on weight.
2. Inflammatory PMOS. This type is associated with persistent, low-grade inflammation and is connected to symptoms like headaches, acne and joint pain among other symptoms. It’s important to note that insulin-resistance and high androgen levels can also increase inflammation, making the division between these types unclear.
3. Adrenal PMOS. This type is associated with high levels of DHEA, a hormone within the larger group of androgens that is created in the adrenal glands. Studies show that some people with PMOS have higher levels of DHEA. People are said to have this type of PMOS if they display DHEA as the main androgen with heightened levels in hormone testing, as opposed to other androgens like testosterone.
4. Pill-induced PMOS: Oral contraceptive pills do not cause PMOS, but they can mask or treat PMOS symptoms. Once you stop taking them, without the regulation of hormones with pills, it can reveal PMOS symptoms, such as elevated androgen levels, weight gain and irregular menstrual cycles. These post-pill symptoms typically resolve after an adjustment period, but be sure to consult with your provider if symptoms persist.
[What Is Insulin and What Does Insulin Do?]
Common Symptoms of PMOS
PMOS symptoms can begin around puberty, after the first menstrual cycle, though some may not notice symptoms until later in adolescence or during their 20s.
Common symptoms of PMOS include:
— Irregular or unpredictable periods, a classic early symptom for most people with PMOS
— Cysts on one or both of the ovaries
— Obesity or difficulty maintaining a healthy weight
— Acne or oily skin
— Skin tags, which are soft skin growths that most commonly appear on the neck, armpits, chest or thighs and are completely harmless
— Excessive facial hair or body hair on the chest, back, thighs or belly button-area
— Hair loss, hair thinning or male-pattern hair loss
— Infertility or subfertility
— Insulin resistance
— Mental health issues like anxiety and depression
Though a few significant symptoms are used to determine a diagnosis, you do not have to have every symptom listed to have PMOS.
“PMOS can present in different ways or have different effects on different people’s lives,” Shenoy says.
Early signs of PMOS in teens and young adults
Early signs of PMOS often emerge during the teenage years or early adulthood. Common early symptoms include:
— Irregular and missed periods
— Acne that doesn’t respond well to treatments
— Excess hair growth on the face and body
— Thinning hair on the scalp
— Unexplained weight gain, or increased fat accumulation around the abdomen
— Dark, velvety patches of skin on the neck, groin and underarms
— Fatigue, mood changes
[SEE: Best Probiotics for Vaginal Health]
How Is PMOS Diagnosed?
Diagnosing PMOS can sometimes be difficult. This is because PMOS is a diagnosis of exclusion, meaning that before a PMOS diagnosis can be made, the possibility of other health conditions that can cause PMOS symptoms must be eliminated.
The diagnostic criteria for PMOS
A PMOS diagnosis is based on patients exhibiting at least two of the following three clinical signs:
— Polycystic ovaries. Polycystic ovaries feature fluid-filled sacs with a distinct appearance. “There’s a classic appearance of a ring of cysts on the outside of the ovaries. This is not just having random cysts on the ovaries. It’s a distinct, PMOS-appearing ovary,” says Taylor.
— Irregular periods. In PMOS, periods may be irregular — more than 35 days or less than 21 days between cycles — or absent completely.
— Excess androgens. Excess androgens can manifest as symptoms like acne or excess hair growth on the face, chest or belly button. Excess androgen can also be detected via lab evidence showing elevated levels of testosterone or other androgen hormones.
In order to determine if you fit the diagnostic criteria and display at least two of the three key symptoms, a practitioner may perform tests:
— Physical exam. Physicians will generally perform physical exams to check for common signs of PMOS like acne and excess facial or body hair. Your provider will also ask you about your symptoms, your menstrual regularity and any weight changes.
— Internal ultrasounds. These tests may be performed to detect the presence of polycystic ovaries.
— Blood tests. Blood tests check for elevated androgen levels. Blood tests may also be used to check for insulin-resistance, blood sugar levels, ovulation-related hormone levels and cholesterol levels.
PMOS can be diagnosed by a few types of healthcare professionals, including gynecologists, endocrinologists and reproductive endocrinologists.
[READ: 10 Questions to Ask at Your OB-GYN Appointment.]
Related Health Risks and Complications
PMOS may put you at an increased risk for other health problems.
These conditions include:
— Type 2 diabetes or prediabetes
— Problems with fertility, miscarriage or preterm birth
— Obstructive sleep apnea
— Endometrial or uterine cancer
— Depression, anxiety or other mood disorders
— Poor body image and eating disorders
— High-risk pregnancies and gestational diabetes
PMOS and infertility: Can you get pregnant?
PMOS is a common cause of infertility because the hormonal imbalances associated with the condition can disrupt ovulation, making it more difficult to conceive. However, a diagnosis of PMOS doesn’t mean pregnancy is impossible. Many people with PMOS conceive naturally, while others may benefit from lifestyle changes, medications to stimulate ovulation or fertility treatments. With an early diagnosis, medical care and management of metabolic and hormonal symptoms, many people with PMOS can become pregnant.
Heart health and Type 2 diabetes
PMOS is increasingly recognized as a cardiometabolic disorder, not just a reproductive condition. Many people with PMOS experience insulin resistance, where the body cell’s don’t respond to insulin effectively, which can lead to higher blood sugar levels and increased insulin production. Over time, this can significantly raise the risk of developing Type 2 diabetes and other cardiometabolic complications such as high blood pressure, abnormal cholesterol levels and cardiovascular disease.
Because of these related health risks, people with PMOS may undergo screening for aforementioned complications associated with PMOS more frequently every three to five years.
[READ: 14 Essential Health Screenings Every Woman Needs]
PMOS Management
While there is no cure for PMOS, there are treatments available to manage its symptoms and help prevent associated health conditions.
“Treatments are usually aimed at what an individual patient’s goal is,” Shenoy says.
Available treatments range from medications to lifestyle changes to surgical procedures. It’s important to consult with your physician before starting any of these treatments, as some are not suitable if you are pregnant or planning on becoming pregnant.
Medications for PMOS (birth control, metformin and anti-androgens)
Irregular periods are one of the major symptoms of PMOS — studies show that 75% to 85% of women with PMOS have menstrual dysfunction. However, there are treatments available that help make periods more regular:
— Birth control pills. Birth control pills are a typical first-line treatment for PMOS as they are inexpensive, easy to use and cover a variety of PMOS symptoms. Birth control pills regulate menstrual cycles and balance hormones. They contain reproductive hormones like estrogen or progesterone, or both, in the case of combination birth control pills. These pills can also help with acne, excess facial hair and lowering the risk of endometrial cancer. Alternatively, other forms of hormonal birth controls such as birth control shots, patches, vaginal rings or IUDs may also be prescribed. In the case that birth control pills alone are not effective in regulating cycles, anti-androgens like spironolactone are commonly used to help block male hormone action.
— Progestin therapy. Progestin is a synthetic form of the reproductive hormone called progesterone that helps control the menstrual cycle. In progestin therapy, patients take progestin for only part of their cycle to induce a period by thickening the lining of the uterus. Once patients finish the prescribed days of progestin, the uterine lining sheds, producing a period.
— Metformin and other insulin-sensitizing medications. For people with PMOS who have insulin resistance, metformin and other insulin-sensitizing medications can help regulate periods by promoting ovulation through decreasing levels of insulin and blood sugar and reducing androgen production.
[SEE: Best Acne Treatments and Creams]
Treatments for acne and excessive hair growth
— Oral medication to treat acne. Physicians may prescribe medications like isotretinoin — also known as Accutane — oral antibiotics and anti-androgens like spironolactone to treat acne. Anti-androgens can also improve excessive hair growth. Because birth control pills help regulate hormones, they may often also be prescribed to treat acne in PMOS cases.
— Topical acne treatments. Topical treatments can also treat acne. These include over-the-counter treatment options like benzoyl peroxide and salicylic acid as well as prescription retinoids and topical gels.
— Laser hair removal and electrolysis. For those experiencing excessive hair growth, laser hair removal or electrolysis can help. Laser hair removal utilizes concentrated light to remove unwanted hair. Electrolysis removes excess hair by damaging the hair root with an electric current.
— Hair removal topical creams and traditional hair removal methods. Hair removal topical creams can also help manage excessive hair growth. Additionally, a cream called eflornithine — sold under brand names like Florexa and Vaniqa, among others — can be used to slow hair growth. Other traditional hair removal products like tweezing, shaving and waxing can also be used.
Fertility treatments for PMOS
PMOS is one of the most common causes of infertility or subfertility — studies estimate that between 70% and 80% of people with PMOS experience infertility. Fertility can be a challenge with PMOS, but there are treatments to help promote fertility, and many people with PMOS still do get pregnant.
Oral ovulatory stimulant medications are typically prescribed first before trying other treatments as they are effective, inexpensive and easy to use.
Fertility treatments include:
— Clomiphene (Clomid). Clomiphene is an oral ovulatory stimulant and is often the first medication doctors prescribe to PMOS patients struggling to get pregnant. This medication stimulates egg development and ovulation by increasing the production of ovulation-related hormones.
— Metformin. Metformin is an oral insulin-sensitizing medication that can promote ovulation and increase the chances of pregnancy. It can be taken alone or is sometimes prescribed alongside clomiphene.
— Letrozole (Femara). Letrozole is another oral ovulatory stimulant that can help stimulate egg development and ovulation to increase fertility.
— Gonadotropins. Gonadotropins are often used for patients who do not see results after taking oral ovulatory stimulants like metformin, clomiphene or letrozole. This medication is administered via subcutaneous injection to encourage follicular growth and ovulation.
— In vitro fertilization (IVF). IVF is the next treatment that is used when other ovulatory stimulants have not been effective in treating infertility. This treatment involves harvesting a patient’s eggs, fertilizing them in a lab, and returning the fertilized eggs — embryos — to the uterus in order for them to grow. IVF can be completed with you and your partner’s sperm and egg or with an egg or sperm donor.
— Ovarian drilling. “In this surgical procedure, small holes are drilled into the ovary, and that disrupts some of the irregular cysts on the outside of the ovary which may promote ovulation,” Taylor says. While the treatment can be effective, other treatments are usually favored because of ovarian drilling’s invasive approach and high cost.
Lifestyle Changes and the Best PMOS Diet
While treatments like oral or topical medications can be helpful in managing PMOS symptoms and improving fertility, there are also lifestyle changes you can make to help improve your PMOS symptoms, reduce your risk for associated conditions and improve your quality of life.
How PMOS affects weight gain and metabolism
Losing weight with PMOS can feel overwhelming and at times discouraging. The hormonal imbalance that PMOS triggers cause some women to report having intense food cravings, due to the overproduction of insulin, and never feeling full or satiated, due to the underproduction of hormones like ghrelin, cholecystokinin and leptin, which regulate to hunger.
It can be a vicious cycle. With insulin resistance, the body often stores fat in the abdominal region — which puts a person at higher risk for heart disease and Type 2 diabetes. A PCOS diet, weight loss and physical activity won’t make PCOS go away, but can help reduce the symptoms.
Hillary Wright, registered dietitian and author of “The PCOS Diet Plan: A Natural Approach for Health for Women with Polycystic Ovary Syndrome,” advises her clients to ignore the scale and focus on managing symptoms and insulin resistance by adopting a healthy lifestyle. “Women with PCOS who are overweight can be healthy. Losing as little as 5% to 10% of their weight will improve their insulin resistance, which in turn is beneficial for their fertility and their overall health.”
Weight loss tips
— Plan meals in advance and stock your kitchen with healthy options.
— Focus on feeling better and less on the numbers on the scale.
— Choose carbs carefully, both in terms of quality and quantity.
— Build new habits that are sustainable, one at a time.
— Add physical activity to your daily routine. The current federal guidelines recommend 150 minutes of moderate heart-pumping exercise each week. That could break down to 30 minutes, five times a week, or you could do it in smaller chunks.
— Manage stress with exercise, yoga, meditation or quiet walks.
Foods to eat with PMOS
Many dietitians find success in controlling PMOS symptoms with a plant-forward diet. This may include eating more whole grains, fruits and vegetables, seafood or plant-based proteins like legumes and nuts, and eating little red meat, refined carbohydrates and processed foods.
Some people may praise a keto diet (a type of low-carb diet) or intermittent fasting, but that’s only anecdotal. If you have PCOS and want to make healthier food changes, you should rely on some of the basics of healthy eating.
Because high blood sugar can worsen insulin resistance, increase the production of androgens in your body and further worsen PMOS symptoms, managing blood sugar levels with diet can help manage PMOS symptoms.
“How we eat can have a big impact on how symptoms like irregular periods, facial hair, weight gain, acne, hair loss, fatigue and cravings show up, and how they can be managed,” Ruth says.
— Fiber. Fiber-rich foods to incorporate into your diet include fruits, low-starch vegetables, beans, whole grains, nuts and seeds.
— Lean proteins. Lean proteins like fish, eggs, chicken and turkey breast, beans and legumes are best as they are low in saturated fats.
— Healthy fats. Foods rich in healthy fats can also help manage blood sugar levels and PMOS symptoms. Healthy fats include avocado, oils like olive oil or walnut oil, seeds and nuts.
— Foods high in omega-3 fatty acids. These foods can help fight inflammation and provide healthy fats. Good sources for omega-3 fatty acids include fatty fish like salmon and herring, walnuts and chia seeds.
— Probiotics. Include probiotics such as yogurt, cheese, kimchi, sauerkraut and other fermented foods to boost the healthy organisms in your gut microbiome.
— More fruits and vegetables. These are often low in calories and full of fiber and antioxidants, which can help fight inflammation. Non-starchy vegetables and fruit such as leafy greens, mushrooms, berries, peppers, tomatoes and avocados are good choices.
On the other hand, there are certain foods that can cause blood sugar to spike and worsen PMOS symptoms. Foods to avoid or limit include:
— Sugary foods and drinks like cookies, cake, sodas, energy drinks and sweetened beverages. Sneaky sources of added sugar include tomato sauce, salad dressing and certain condiments.
— Highly-processed foods like chips and white bread
— Fried foods like french fries or fast foods
— Fatty or processed meats like bologna, hot dogs or fatty-cuts of meat
Even if you don’t have insulin-resistant PMOS, regulating blood sugar levels through diet can help improve PMOS symptoms, as high blood sugar can raise insulin levels and further contribute to hormonal imbalances and increased inflammation.
“Blood sugar dysregulation can make PMOS symptoms worse, even if you are someone who isn’t insulin resistant or struggling with weight,” says Ruth. “This is because there’s still that huge connection from what we’re eating — and our blood sugar — and our hormones, like insulin and androgens.”
Here is a sample daily meal plan from Wright. This meal plan has approximately 1,800 calories, 108 grams protein and 37 grams fiber:
— Breakfast: Oatmeal with walnuts, fresh orange and skim milk
— Snack: Pineapple and nuts
— Lunch: Whole-wheat tortilla with hummus, turkey, cheese, lettuce and tomato. One pear
— Snack: Peanut butter and whole-wheat crackers
— Dinner: Salmon with carrots. Broccoli with cheese. Brown rice. Skim milk
Weight loss medications — like Mounjaro or Ozempic — may be helpful.
Physical activity
Staying physically active plays an important role in managing PMOS symptoms.
Regular physical activity provides a range of health benefits for those with PMOS, including:
— Regulation of blood sugar levels
— Lowered insulin levels
— Lowered androgen level
— Improved sleep
— Improved fertility
— Reduced risk of developing conditions associated with PMOS like Type 2 diabetes or heart disease
— Weight management
“The best exercise for PMOS is the one that you like and the one that you’re going to be more consistent in getting in,” Ruth says.
Sleep hygiene
Making sure you’re getting enough sleep can also help improve PMOS symptoms, as good sleep can improve hormonal balances and reduce inflammation.
“Good sleep is really the foundation of good hormonal health,” Ruth explains. You can improve your sleep by creating a bedtime routine to help you wind down before bed and minimizing screen time before sleep.
[READ: Beyond Yoga: 22 Practical Ways to Relieve Stress and Calm Anxiety]
Managing stress
Managing stress can also help improve PMOS symptoms. “For some with PMOS, stress will negatively impact them more than others,” Ruth says.
Stress causes increased production of a hormone called cortisol, which can worsen PMOS symptoms like mood swings and fatigue. “The importance of working on your stress levels can’t be understated — decreasing stress is only ever going to be a good thing,” Ruth says.
You can manage stress in many ways, like developing a self-care routine and incorporating destressing, relaxing activities that you enjoy into your daily life. Taking care of your mental wellbeing is critical with PMOS.
“Many people benefit from counseling, support and medication,” says Dr. Eli Reshef, a reproductive endocrinologist and infertility specialist at the Advanced Fertility Center of Chicago and a member of the Medical Advisory Board at WIN.
Frequently Asked Questions About PMOS
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What Is PMOS? (Formerly PCOS) Symptoms, Causes and Treatments originally appeared on usnews.com
Update 06/16/26: This story was published at an earlier date and has been updated with new information.
