Last week, a global consensus paper in The Lancet officially renamed Polycystic Ovary Syndrome. It is now called Polyendocrine Metabolic Ovarian Syndrome — PMOS. [1] One letter added. But behind that letter is a argument that has been building in endocrinology for two decades: that this condition was never primarily about the ovary, and the name was quietly misleading everyone — the patient, the GP, the gynaecologist.
The renaming process involved 56 academic and clinical organisations, drew over 22,000 survey responses from patients and clinicians over eleven years, and ended with 86% of patients and 71% of clinicians backing the change. [2] That is not a committee reshuffling terminology. It is just correcting a foundational mistake.
What the Old Name Got Wrong
The "cysts" in polycystic ovary syndrome were never true cysts. They were arrested follicles — small egg-containing sacs that stalled mid-development and never completed ovulation. On ultrasound they looked like a string of pearls around the ovary, and decades ago someone called them cysts. The name entered textbooks, entered clinical practice, and stayed.
The problem is what that name implied. To a GP, to a gynaecologist, to the patient herself — PCOS sounded like an ovarian condition. A reproductive problem. Something to manage with a contraceptive pill and a referral to fertility services if and when pregnancy became the goal. The metabolic dimension — the insulin resistance, the cardiometabolic risk, the trajectory toward diabetes — rarely made it into the first conversation, or often any conversation at all.
That gap has consequences. We are not talking about a rare disease. PMOS affects over 170 million women worldwide, roughly 1 in 8 of all women in their reproductive years. [1, 2] In India specifically, prevalence estimates in urban populations run as high as 22.5% by Rotterdam criteria — nearly 1 in 5 young women. [9] The global average is 8 to 13%. Indian women are well above it, and we do not fully understand why.
Where Diabetes Enters
PMOS is fundamentally an insulin resistance syndrome. The root pathology is a defect in how insulin signals inside cells — specifically an abnormality in serine phosphorylation at the insulin receptor level — that makes muscle and fat tissue resistant to insulin's effects. [3] This has nothing to do with how much a woman weighs. Insulin resistance is detectable in 50 to 80 percent of women with PMOS, including those who are completely lean. [3]
The body's response to insulin resistance is to produce more insulin. Blood glucose stays normal — for a while. But that prolonged hyperinsulinism drives the ovaries, which remain insulin-sensitive unlike the rest of the body, to produce excess androgens. Those androgens suppress ovulation, arrest the follicles, drive the acne and the hair changes. And then they loop back and worsen insulin resistance further. The reproductive symptoms result from a metabolic problem that starts well before the ovary is involved.
Glucose is the last thing to change in this chain. By the time a fasting blood sugar becomes abnormal, insulin resistance has often been present for a decade or more. [6] This is why waiting for glucose to rise before investigating—which is standard practice in most settings—means missing the window where intervention actually changes outcomes.
The diabetes numbers in PMOS are difficult to read without some discomfort. Type 2 diabetes affects 1 to 3 percent of women of reproductive age in the general population. In women with PMOS, that figure is 12.4 percent. [4] Women with PMOS are three times more likely to have impaired glucose tolerance — the stage before diabetes, where vascular damage is already beginning. And more than half of all women with PMOS will have developed type 2 diabetes by age 40. [4] With 170 million women affected globally, that means well over 85 million women on a diabetes trajectory, the majority of whom were never told about this risk when they received their diagnosis.
The Indian Picture
For Indian women, the risk sits even higher.
The Wijeyaratne database from Colombo — the most comprehensive South Asian PMOS phenotype study available — found that nearly a third of South Asian women with PMOS meet full criteria for metabolic syndrome, and acanthosis nigricans, the skin darkening at the neck and armpits that signals severe insulin resistance, was present in 64% of cases. [8] These women were developing central obesity at BMIs that would not even trigger concern in a Western clinic. In practice, I see this regularly — a young woman, not overweight by standard charts, but with acanthosis at the nape of the neck and a fasting insulin that tells the real story before the glucose ever moves.
India also has its own PMOS burden that goes beyond phenotype. The pooled prevalence from Indian studies is around 11%, but urban figures are considerably higher, and the condition is rising with sedentary lifestyles, dietary change, and increasing rates of adolescent obesity. [9] Despite this, metabolic screening at the time of PMOS diagnosis remains inconsistent across most Indian practices — an OGTT is rarely done, fasting insulin almost never.
What Changes Now
The Lancet consensus mandates updates to clinical guidelines, medical education curricula, and the ICD classification system. [1] Reclassifying PMOS away from a purely gynaecological code changes the institutional logic around who is responsible for this patient's care.
In practical terms, the expectation under PMOS is that metabolic assessment — glucose tolerance, fasting insulin, lipid profile, blood pressure, waist circumference — happens at diagnosis, not years later. Fasting glucose alone is inadequate; postprandial glucose rises first, and in Indian women particularly, a 75g OGTT with a two-hour reading is the appropriate screen. HOMA-IR, calculated from fasting insulin and glucose, is a reasonable proxy for insulin resistance in clinical practice even where formal clamp studies are not available.
The referral question also changes. An endocrinologist belongs in this patient's care from early on — not only when fertility becomes the issue, or when glucose eventually tips over. The 2023 International PCOS Guidelines had already recommended metabolic assessment at diagnosis; the rename may be what finally makes this routine. [7]
There is a three-year transition period where PCOS and PMOS will be used alongside each other. [2] Existing patients do not need to re-diagnose. The biology hasn't changed. How we're expected to think about it has changed.
Final thought
For seventy years, "polycystic" pointed everyone toward the ovary and away from the pancreas, the vasculature, and the long metabolic future of these women.
The difference between PCOS and PMOS is not administrative. It means a 28-year-old walks out knowing her glucose future, not just her period calendar—and she has the chance to change that path before glucose ever rises.
That conversation should have been happening all along. It can start now.
References
- Teede HJ, Bahri Khomami M, Morman R, et al. Polyendocrine metabolic ovarian syndrome, the new name for polycystic ovary syndrome: a multistep global consensus process. Lancet. Published online May 12, 2026. doi:10.1016/S0140-6736(26)00717-8 — thelancet.com
- Endocrine Society Press Release. Polyendocrine Metabolic Ovarian Syndrome: New name to improve diagnosis and care. May 12, 2026 — endocrine.org
- Genazzani AD, Genazzani AR. Polycystic Ovary Syndrome as Metabolic Disease: New Insights on Insulin Resistance. touchREV Endocrinol. 2023;19(1):71–77. doi:10.17925/EE.2023.19.1.71. PMC: PMC10258623
- PCOS and Diabetes. Endocrinology Advisor. endocrinologyadvisor.com
- Rojas J et al. Polycystic Ovary Syndrome, Insulin Resistance, and Obesity: Navigating the Pathophysiologic Labyrinth. Int J Reprod Med. 2014. PMC: PMC4334071
- Parker J, Briden L, Gersh FL. Recognizing the Role of Insulin Resistance in PCOS: A Paradigm Shift from a Glucose-Centric Approach to an Insulin-Centric Model. J Clin Med. 2025;14(12):4021. doi:10.3390/jcm14124021. PMC: PMC12194245
- Teede HJ et al. Recommendations from the 2023 International Evidence-Based Guideline for PCOS. Fertil Steril. 2023;120:767–93. doi:10.1016/j.fertnstert.2023.07.025
- Wijeyaratne CN, Seneviratne RdA, Dahanayake S, et al. Phenotype and metabolic profile of South Asian women with polycystic ovary syndrome (PCOS): results of a large database from a specialist Endocrine Clinic. Hum Reprod. 2011;26(1):202–13. doi:10.1093/humrep/deq310. PubMed
- Dhakal A, et al. Prevalence of Polycystic Ovarian Syndrome in India: A Systematic Review and Meta-Analysis. PMC. 2023. PMC: PMC9826643