Rotterdam PCOS Criteria Calculator
Rotterdam PCOS Criteria Calculator
Two of three features diagnose polycystic ovary syndrome in an adult — but only after other causes are excluded, and only ever with one of ultrasound or AMH, never both. In an adolescent the third feature does not exist at all, and this page will refuse it.
Rotterdam criteria, 2023 guideline
Life stage + features → diagnosisAdult, irregular cycles, hirsutism with a raised free androgen index, no ultrasound or AMH, TSH and prolactin and 17-OHP normal
The criteria, as the 2023 guideline states them
Adolescents — both hyperandrogenism and ovulatory dysfunction; ultrasound and AMH are not recommended
Both — after exclusion of other causes
- the exclusive OR
- either serum AMH or ultrasound may define polycystic ovarian morphology, but both should not be performed, to limit over-diagnosis. This is a guideline practice point (1.5.5), not an editorial preference, and it is why this page offers one selector rather than two
- FNPO ≥ 20
- follicle number per ovary of 20 or more in at least one ovary is the adult ultrasound threshold, and follicle number per ovary is the most effective ultrasound marker
- OV ≥ 10 mL
- ovarian volume of 10 mL or more, or 10 or more follicles per cross-section, in at least one ovary — the fallback threshold where the technology is older or the image quality insufficient, and the figure a transabdominal scan should report
- AMH
- permitted for defining polycystic ovarian morphology in adults, never as a single test for the diagnosis, and never in adolescents. No guideline-endorsed numeric threshold exists: laboratories are told to use population- and assay-specific cut-offs, which is why this page asks a yes or no against yours
- exclusion
- TSH, prolactin and 17-hydroxyprogesterone, plus FSH where relevant, and clinical exclusion of Cushing’s syndrome and adrenal or ovarian tumours. This is part of the diagnosis, not a footnote to it
Worked example
Adult, irregular cycles, hirsutism with a raised free androgen index, no ultrasound or AMH, TSH and prolactin and 17-OHP normal
Ovulatory dysfunction — present
Hyperandrogenism — present, clinical and biochemical
That is already two of three, so polycystic ovarian morphology does not need to be assessed at all
The guideline says this in as many words: an ovarian ultrasound is not necessary for PCOS diagnosis in patients with irregular menstrual cycles and hyperandrogenism, and nor is an AMH
Other causes excluded → Rotterdam criteria met
The next step is metabolic and psychological assessment, not another scan
What each criterion requires, and where it changes with life stage
| Criterion | Adults | Adolescents | Guideline |
|---|---|---|---|
| Ovulatory dysfunction | Cycles under 21 or over 35 days, or fewer than 8 a year, from 3 years post menarche to perimenopause | Under 21 or over 45 days from 1 to under 3 years post menarche; the first year post menarche is normal | 1.1.1 |
| Clinical hyperandrogenism | Hirsutism alone is predictive; acne and female pattern hair loss in isolation are weak predictors | Severe acne and hirsutism | 1.3.1, 1.3.2, 1.3.3 |
| Biochemical hyperandrogenism | Total and free testosterone, ideally by LC-MS/MS; free testosterone may be estimated by the calculated free androgen index | Androgen levels reach adult ranges at 12 to 15 years of age | 1.2.1, 1.2.3, 1.2.8 |
| PCOM on ultrasound | FNPO ≥ 20 in at least one ovary; or ovarian volume ≥ 10 mL or FNPS ≥ 10 on older technology | Not recommended — no definitive criteria exist at this life stage | 1.4.4, 1.4.5, 1.4.6 |
| Raised AMH | May define PCOM, against a population- and assay-specific cut-off. Never as a single test | Should not yet be used | 1.5.1, 1.5.3, 1.5.4, 1.5.7 |
| Exclusion of other causes | TSH, prolactin, 17-OHP, FSH; clinically Cushing’s and adrenal or ovarian tumours | The same | Diagnostic algorithm |
The mimics, and the test that separates each
| Condition | Test | What points to it |
|---|---|---|
| Thyroid disease | TSH | Cycle disturbance with weight, bowel or thermal symptoms. Both hypo- and hyperthyroidism disturb cycles |
| Hyperprolactinaemia | Prolactin | Oligomenorrhoea or amenorrhoea with galactorrhoea. Check for macroprolactin before imaging a modest elevation |
| Non-classic congenital adrenal hyperplasia | 17-hydroxyprogesterone | Hirsutism and irregular cycles indistinguishable from PCOS. Sample early morning, follicular phase. Treated differently, so worth finding |
| Hypogonadotrophic hypogonadism | LH and FSH | Amenorrhoea with low body fat or intensive exercise. Gonadotrophins low rather than normal or high |
| Cushing’s syndrome | Clinical, then overnight dexamethasone or late-night salivary cortisol | Proximal myopathy, striae, easy bruising, centripetal fat. Rare, but the consequence of missing it is severe |
| Androgen-secreting tumour | Total testosterone, DHEAS, imaging | Rapid onset, virilisation, or androgens markedly rather than modestly above the reference range |
Two of three — and why the third criterion is a choice, not a pair of tick-boxes
The Rotterdam criteria have been in use since 2003 and the arithmetic has not changed: two of three features, in an adult, after other causes are excluded. What the 2023 International Evidence-based Guideline changed is the content of the third feature and the rules for using it, and those changes are the reason this page exists in the shape it does. Polycystic ovarian morphology may now be established either by ultrasound or by a raised anti-Müllerian hormone — and the guideline states, as a practice point, that both tests should not be performed, precisely because doing both inflates the number of women who meet a criterion and therefore inflates the number who receive a diagnosis. That is why the third input above is a single selector with five mutually exclusive options rather than two independent boxes. A tool that let you tick both would be encouraging the specific behaviour the guideline warns against.
The life-stage selector is more consequential still. In adolescents neither ultrasound nor AMH is recommended: multifollicular ovaries are a normal finding in the years after menarche, AMH is at its population peak in the early twenties, and the specificity of both is too poor to carry a diagnosis. So at that life stage the third Rotterdam feature does not exist, and both of the remaining two are required. This page will not accept an ultrasound or an AMH result in an adolescent — not because the number is wrong, but because it is not a criterion, and treating it as one is how a sixteen-year-old acquires a lifelong label from a scan that described a normal ovary. The guideline also offers a category for the adolescent who has one feature and not the other: increased risk, with reassessment at or before eight years post menarche. That is a legitimate answer and this page gives it.
The other thing worth stating plainly is when the third test is unnecessary. If an adult has both irregular cycles and hyperandrogenism, the criteria are already met, and the guideline says in as many words that an ovarian ultrasound is not necessary — and repeats it for AMH. A normal scan does not unmake the diagnosis, a low AMH does not either, and ordering one invites exactly the confusion it cannot resolve. The test that does still matter at that point is the exclusion panel. Thyroid disease, hyperprolactinaemia and non-classic congenital adrenal hyperplasia all present with cycle disturbance and hyperandrogenism, and the last of those is managed differently from PCOS. A TSH, a prolactin and an early-morning follicular-phase 17-hydroxyprogesterone are the minimum, and Cushing’s syndrome and an androgen-secreting tumour are excluded clinically.
Finally, note where the biochemistry belongs. Hyperandrogenism may be clinical or biochemical, and hirsutism on its own counts — the guideline treats it as predictive of biochemical hyperandrogenism in adults, which means a modified Ferriman-Gallwey score at or above the current threshold can satisfy the criterion without a blood test. Where androgens are measured, the guideline asks for total and free testosterone, ideally by tandem mass spectrometry rather than a direct immunoassay, with free testosterone estimated by the free androgen index or calculated free testosterone. And it is very difficult to assess biochemical hyperandrogenism at all in a woman on the combined pill, which raises sex hormone-binding globulin and suppresses gonadotrophin-dependent androgen production; if the measurement is essential, the pill has to come off for at least three months first.
Frequently asked questions
What are the Rotterdam criteria for PCOS?
Two of three features in an adult: ovulatory dysfunction or irregular cycles; clinical or biochemical hyperandrogenism; and polycystic ovarian morphology, established either on ultrasound (follicle number per ovary of 20 or more, or ovarian volume of 10 mL or more, in at least one ovary) or by a raised AMH against the laboratory’s own cut-off. Other causes must be excluded before the diagnosis is made.
Can AMH and ultrasound both be used to diagnose PCOS?
No — one or the other. The 2023 guideline states that either serum AMH or ultrasound may be used to define polycystic ovarian morphology, but that both tests should not be performed, to limit over-diagnosis. Running both gives two chances to meet one criterion, which raises the number of women labelled without improving the accuracy of the label.
Is there an AMH level that diagnoses PCOS?
There is no guideline-endorsed number. The 2023 guideline permits AMH for defining polycystic ovarian morphology in adults but gives no threshold, and instructs laboratories to use population- and assay-specific cut-offs instead. AMH results differ substantially between the Gen II, picoAMH, Elecsys and Access platforms, so a threshold from one assay does not transfer to another.
How is PCOS diagnosed in adolescents?
Both hyperandrogenism and ovulatory dysfunction are required, because ultrasound and AMH are not recommended at this life stage — multifollicular ovaries and a high AMH are both normal after menarche. An adolescent with one feature but not the other can be considered at increased risk, with reassessment at or before eight years post menarche.
What blood tests exclude other causes of PCOS symptoms?
TSH for thyroid disease, prolactin for hyperprolactinaemia, and an early-morning follicular-phase 17-hydroxyprogesterone for non-classic congenital adrenal hyperplasia, with FSH where hypogonadotrophic hypogonadism is plausible. Cushing’s syndrome and an androgen-secreting tumour are excluded clinically, and investigated urgently if hyperandrogenism is severe or rapidly progressive.
Does a normal ovarian ultrasound rule out PCOS?
No. Polycystic ovarian morphology is only one of three criteria and only two are needed, so a woman with irregular cycles and hyperandrogenism has PCOS whatever her ovaries look like. The guideline goes further and says the ultrasound is not necessary in that situation at all.
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References
- Teede HJ, Tay CT, Laven JJE, et al. Recommendations From the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. J Clin Endocrinol Metab. 2023;108(10):2447–2469. doi:10.1210/clinem/dgad463 — recommendations 1.1.1, 1.1.4, 1.2.1, 1.3.1–1.3.7, 1.4.4–1.4.9, 1.5.1–1.5.7, 1.6.1.
- Monash University Centre for Research Excellence in Women’s Health. International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome 2023 — guideline summary and diagnostic algorithm. “In adults this requires the presence of two of i) clinical/biochemical hyperandrogenism, ii) ovulatory dysfunction and iii) polycystic ovaries on ultrasound or elevated anti-mullerian hormone (AMH) levels”; “In adolescents, both hyperandrogenism and ovulatory dysfunction are required, with ultrasound and AMH not recommended, due to poor specificity.”
- Rotterdam ESHRE/ASRM-Sponsored PCOS Consensus Workshop Group. Revised 2003 consensus on diagnostic criteria and long-term health risks related to polycystic ovary syndrome. Fertil Steril. 2004;81(1):19–25.
- Barbagallo F, van der Ham K, Willemsen SP, Louwers YV, Laven JSE. Age-related Curves of AMH Using the Gen II, the picoAMH, and the Elecsys Assays in Women With Polycystic Ovary Syndrome. J Clin Endocrinol Metab. 2024;109(10):2561–2570. doi:10.1210/clinem/dgae153 — Elecsys reads lower than Gen II and picoAMH; cut-offs are not transferable between assays.
Medical Disclaimer: The tools and content provided here are for educational and reference purposes only. They are not intended to substitute for professional medical advice, diagnosis, or treatment. Clinical decisions should always be based on the comprehensive assessment of a qualified healthcare professional.