Polyendocrine Metabolic Ovarian Syndrome (PMOS)
Formally known as Polycystic Ovary Syndrome (PCOS)
Medically Reviewed and Contributed by Dr. Jason Griffith, Shady Grove Houston
Polyendocrine Metabolic Ovarian Syndrome (PMOS), formerly known as Polycystic Ovarian Syndrome (PCOS), is a complex, long-term endocrine and metabolic condition. It can look different from person to person, which is part of what has made it so difficult to diagnose and treat for so long.
If you have been living with a PMOS diagnosis or are just learning about PMOS for the first time, this page is here to help you understand what it is, what it means for your health, and what options exist for managing it.
PMOS is a syndrome, which means it is defined by a collection of characteristics rather than a single cause. PMOS has three main features.
Irregular menstrual cycles caused by ovulation dysfunction
PMOS can cause irregular changes in hormone levels that lead to irregular, skipped, or absent periods as well as abnormal bleeding. These disruptions to ovulation are one of the primary reasons PMOS is frequently associated with infertility.
Visible and biochemical changes
Some people with PMOS experience oily skin, acne, or body hair growth on the face, chest, or abdomen. Bloodwork may also reveal elevated male hormone levels, including testosterone, which is a biochemical indicator of the condition.
Ovarian appearance on ultrasound
When viewed through ultrasound, the ovaries of someone with PMOS may appear to have multiple small cyst-like structures. These are actually antral follicles that contain eggs rather than true cysts.
PMOS is diagnosed using criteria-based guidelines known as the Rotterdam Criteria, named after an international consensus conference that established the diagnostic standard. To receive a PMOS diagnosis, a patient typically presents with two of the three typical characteristics described above: irregular menses, visible or biochemical changes, or the appearance of cyst-like structures on the ovaries.
An estimated 1 in 8 women may present with the criteria for PMOS, which translates to approximately 170 million women worldwide. Despite how common it is, many remain undiagnosed and undertreated, often because the symptoms can seem unrelated or are dismissed over time
PMOS is not just a reproductive condition. It is a metabolic one too. In addition to the Rotterdam Criteria, metabolic factors are also considered part of the condition. The most common is insulin resistance.
People with PMOS may also be at elevated risk for cardiovascular disease, Type II diabetes, weight gain, and endometrial cancer.
Understanding these broader health implications is one of the reasons the name change from PCOS to PMOS matters. The new name is designed to reflect the full complexity of the condition and encourages more comprehensive care.
For those who are overweight, weight loss through diet, exercise, and in some cases medication can reduce insulin resistance, and some people will return to regular ovulation through weight loss alone.
For those with demonstrated insulin resistance, insulin-sensitizing medications such as metformin can help restore ovulation.
People who want to become pregnant often need additional support to induce ovulation. Common options include letrozole and clomiphene. In more complex cases, injectable hormones or surgical intervention may be considered.
For those who are not currently trying to conceive, managing the menstrual cycle is still important. Because of fluctuations in the cycle, abnormal amounts of endometrial buildup can occur over time, which increases the risk of endometrial cancer. Addressing this is an important part of long-term care.
The shift from PCOS to PMOS is more than a terminology update. It reflects a deeper and more accurate understanding of the condition.
For years the name Polycystic Ovarian Syndrome (PCOS) led many patients and providers to focus primarily on the ovaries, when in reality PMOS is a systemic condition with wide-ranging effects on metabolic and reproductive health. That narrow framing contributed to missed diagnoses and undertreated patients.
The new name, Polyendocrine Metabolic Ovarian Syndrome, better captures the full scope of what the condition involves. It is a step toward more comprehensive diagnoses, more complete treatment plans, and better long-term outcomes for the millions of people living with it.
If you have questions about what this name change means for your care, we encourage you to speak with your healthcare provider.
PMOS is common, complex, and often isolating. But you do not have to navigate it without support.
RESOLVE offers free support groups, trusted resources, and a community of people who understand what it means to live with a condition that affects your fertility and your overall health. Whether you are newly diagnosed, trying to conceive, or simply looking for more information, we are here for you.