What is the difference between PCOD and PCOS?

Note on the name: in May 2026, polycystic ovary syndrome (PCOS) was formally renamed polyendocrine metabolic ovarian syndrome (PMOS), following a global consensus process. The old name was inaccurate — the condition affects multiple hormone and metabolic systems, not just the ovaries, and "polycystic" wrongly implies ovarian cysts. Nothing about the condition, its diagnosis or its treatment has changed. Both names will be used side by side for the next few years, and we use PCOS below since that is the term most people know.

In everyday use in India the terms are used interchangeably, but there is a real distinction. PCOD usually refers to the ultrasound appearance alone — multiple small follicles around the ovary. That appearance is common and, by itself, is not a diagnosis. A substantial proportion of women without any hormonal problem have polycystic-looking ovaries. PCOS is the clinical syndrome, diagnosed on the Rotterdam criteria: two of three from irregular or absent ovulation, clinical or biochemical signs of raised androgens (acne, excess hair, or raised testosterone on testing), and polycystic ovaries on ultrasound. An important update: current international guidance accepts a raised AMH as an alternative to ultrasound for the ovarian criterion in adults. This is useful where a transvaginal scan is not appropriate or not available. Ultrasound should not be used for the ovarian criterion within about eight years of a girl's first period, because multifollicular ovaries are normal at that age and lead to over-diagnosis in adolescents. The distinction matters because PCOS carries metabolic implications that a scan appearance alone does not.