PCOS Indicator Calculator (Rotterdam Criteria)
Assess how your presentation maps onto the Rotterdam criteria for polycystic ovary syndrome — which require two of three features plus exclusion of other causes.
Formula & Reference
| Variable | Symbol | Formula | Units |
|---|---|---|---|
| PCOS Indicator Calculator (Rotterdam Criteria) | — | Rotterdam: 2 of 3 — ovulatory dysfunction, hyperandrogenism, polycystic ovarian morphology | criteria met |
Step-by-Step Examples
Fewer than 8 periods a year, moderate hirsutism, ultrasound not performed, other causes excluded.
- Ovulatory dysfunction ✓
- Clinical hyperandrogenism ✓
- Ovarian morphology not assessed
- 2 of 3 features met with exclusions done
Regular cycles, no androgen signs, ultrasound shows polycystic morphology.
- Ovulatory dysfunction ✗
- Hyperandrogenism ✗
- Polycystic morphology ✓
- Polycystic ovaries alone do not constitute PCOS
Irregular cycles, mild acne, no bloods or ultrasound, no exclusion testing.
- Ovulatory dysfunction ✓
- Mild clinical androgen signs ✓
- But no laboratory or imaging assessment, and no exclusions
- Assessment is incomplete despite meeting two features on symptoms
Real-World Applications
Common Mistakes to Avoid
Polycystic ovarian morphology appears on ultrasound in a substantial share of women without the syndrome. It is one of three criteria, not a diagnosis.
Rotterdam requires excluding thyroid disease, hyperprolactinaemia, non-classical congenital adrenal hyperplasia, and androgen-secreting tumours. Without that, the diagnosis is not established.
Polycystic ovarian morphology is common in normal adolescence, so current guidance advises against using ultrasound for PCOS diagnosis within about eight years of menarche.