Can you have PCOS without ovarian cysts?

You can have PCOS with completely normal-looking ovaries. Polycystic ovarian morphology is one of the three Rotterdam criteria, and a diagnosis needs any two. A woman with irregular cycles and hyperandrogenism meets the criteria without an ultrasound being done. The 2023 International Evidence-based Guideline states directly that imaging is not required when those two features are already present.

The follicles counted on ultrasound are not cysts

What a sonographer counts in PCOS are antral follicles, the small fluid-filled sacs that every ovary contains and that hold immature eggs. They are two to nine millimetres across and they are supposed to be there. In PCOS more of them accumulate because ovulation is not happening reliably, so they queue rather than mature. A true ovarian cyst is a different structure, usually larger, often single, and not part of the PCOS definition at all.

The threshold that defines polycystic ovaries

For adults, the 2023 guideline sets polycystic ovarian morphology at 20 or more follicles in at least one ovary on a good quality transvaginal scan. Where imaging quality is limited, an ovarian volume of 10 mL or more can be used. That threshold rose over the years as ultrasound resolution improved, which is one reason older reports calling ovaries polycystic at 12 follicles do not carry the same meaning today.

You can also have polycystic ovaries without PCOS

The reverse mistake is more common than the one people worry about. Polycystic-looking ovaries are found in many young women with regular ovulatory cycles and no androgen excess, and that finding on its own is not PCOS. The 2023 guideline recommends against using ultrasound or AMH for diagnosis in adolescents at all, because normal puberty produces the same appearance. An incidental report of polycystic ovaries in a woman with regular periods and normal androgens needs no treatment.

Why the name changed in 2026

In May 2026 an international consensus led by Monash University, involving more than 56 patient and professional organisations and over 22,000 survey responses, renamed the condition polyendocrine metabolic ovarian syndrome, or PMOS. Part of the stated rationale was that the old name misled people into thinking the condition is about abnormal ovarian cysts, which it is not. The diagnostic criteria did not change, and the new name will be fully implemented in the next guideline update.

If your only abnormal result is an ultrasound report, ask two questions before accepting a PCOS label: are my cycles irregular by the guideline definition, and do I have hyperandrogenism on examination or on a mass spectrometry testosterone. Without one of those, an ovarian appearance alone does not make the diagnosis.