PCOS stands for Polycystic Ovary Syndrome — and for a condition affecting 1 in 8 women of reproductive age, it's extremely poorly understood.
The average woman with PCOS sees three or more health professionals and waits over two years to get diagnosed. Despite being one of the most common endocrine disorders in women of reproductive age, many never get diagnosed at all.
Part of the problem is the name. Despite being called Polycystic Ovary Syndrome, PCOS isn't really about cysts. It's a metabolic and hormonal condition that may involve the ovaries. That's why in May 2026, PCOS was renamed PMOS — Polyendocrine Metabolic Ovarian Syndrome. [Link to blog]
That shift in framing — from an ovarian condition to a metabolic one — is what changes thinking and approach. It's also what makes PCOS unusually responsive to the things you can measure and change.
PCOS presents differently in different women.
Fertility problems: Irregular, infrequent, or absent periods. Trouble getting pregnant.
Skin and hair: Excess hair on the face, chest, or stomach. Facial and chest acne. Thinning hair on the scalp.
Weight: Weight gain around the middle that's hard to shift. Fatigue. Sugar cravings. Glucose that’s up and down. Skin tags and darkened patches in folds of skin, like the neck or underarms, are a visible cue for insulin resistance.
The Rotterdam criteria are the international standard. You need two of these three, with other conditions ruled out:
AMH — anti-Müllerian hormone — is produced by the small follicles in the ovaries. The more follicles, the higher the AMH. Women with PCOS typically have two to three times the AMH of women without it, which is why a single blood test can stand in for an ultrasound count of follicles.
The 2023 International Evidence-Based Guideline added AMH as a blood-test alternative to ultrasound — a meaningful upgrade that cuts time to diagnosis, with no waiting for a scan appointment.
Insulin resistance is the mechanism that drives PCOS – but because of the focus on cysts, the attention has been taken away from metabolism. But this framing can guide users to lifestyle interventions that can support treatment.
Insulin tells your cells to absorb glucose. When they stop listening, the pancreas pumps out more insulin to compensate. That elevated insulin directly pushes the ovaries to make more androgens. This fuels hormonal disruption, irregular cycles, skin and hair symptoms, and difficulty losing weight.