PCOS Blood Test Australia: Complete Diagnostic Criteria & Hormone Panel Guide

If you have been told you might have Polycystic Ovary Syndrome (PCOS) — or you suspect it after experiencing irregular periods, acne, hair loss, weight gain, or difficulty conceiving — this guide explains exactly what blood tests an Australian GP will order, how PCOS is diagnosed, and how to read your results.

PCOS affects roughly 8-13% of Australian women of reproductive age, making it one of the most common hormonal conditions in the country. Despite this, an estimated 70% of cases remain undiagnosed, partly because the diagnostic process is misunderstood and partly because blood tests alone do not give a single clear "yes or no" answer.

How is PCOS diagnosed in Australia?

Australian clinical guidelines — the RACGP (Royal Australian College of General Practitioners), RANZCOG (Royal Australian and New Zealand College of Obstetricians and Gynaecologists) and the internationally adopted 2023 International Evidence-based Guideline for the Assessment and Management of PCOS (Monash University, Melbourne) — all use the Rotterdam criteria.

To be diagnosed with PCOS, you need at least 2 of these 3 features:

1. Irregular or absent ovulation — typically cycles longer than 35 days, fewer than 8 cycles per year, or absent periods (after the first 2-3 years post-menarche).
2. Clinical or biochemical hyperandrogenism — clinical signs (hirsutism, acne, scalp hair loss / androgenic alopecia) or elevated androgens on a blood test.
3. Polycystic ovaries on ultrasound — 20+ follicles per ovary or ovarian volume above 10 mL on a transvaginal ultrasound (using modern imaging thresholds).

Crucially, other causes must be excluded first — thyroid disease, hyperprolactinaemia, congenital adrenal hyperplasia, Cushing's syndrome and androgen-secreting tumours can all mimic PCOS. This is why the standard PCOS blood panel includes more than just sex hormones.

The standard PCOS blood test panel in Australia

When you visit your Australian GP with suspected PCOS, the typical pathology request looks like this. Most of these tests are bulk-billed under Medicare when ordered for clinical investigation:

1. Sex hormone panel (the core PCOS markers)

• Total testosterone — elevated in roughly 60-70% of women with PCOS. Reference range: 0.5-2.5 nmol/L. Best measured in the morning.
• SHBG (Sex Hormone Binding Globulin) — typically low in PCOS due to insulin resistance, which amplifies free testosterone activity even when total testosterone looks normal.
• Free Androgen Index (FAI) — calculated as (total testosterone ÷ SHBG) × 100. An FAI above 5 is one of the most useful biochemical markers of hyperandrogenism in PCOS.
• DHEAS — adrenal androgen, often mildly elevated in PCOS and helpful to exclude adrenal tumours.
• 17-OH progesterone — used to exclude non-classical congenital adrenal hyperplasia, which can mimic PCOS.

2. Pituitary hormones

• LH (Luteinising Hormone) — often elevated in PCOS.
• FSH (Follicle Stimulating Hormone) — usually normal or low. The LH:FSH ratio is classically >2:1 in PCOS, though this is no longer required for diagnosis.
• Prolactin — to exclude hyperprolactinaemia, which causes irregular cycles and can mimic PCOS.
• TSH (Thyroid Stimulating Hormone) — to exclude thyroid dysfunction, another common cause of menstrual irregularity.

3. Ovarian reserve marker

• AMH (Anti-Müllerian Hormone) — typically elevated in PCOS (often >35 pmol/L) because of the increased number of small follicles. Note that AMH testing is not currently bulk-billed under Medicare for PCOS investigation in Australia and usually costs A$60-90 out of pocket.

4. Metabolic panel

This is essential because PCOS is fundamentally a metabolic condition for many women, and 35-50% have insulin resistance. Untreated, this raises the risk of type 2 diabetes, cardiovascular disease, fatty liver and pregnancy complications.

• Fasting insulin — frequently elevated in PCOS even with normal glucose. The fasting insulin to glucose ratio (HOMA-IR) is the most sensitive insulin-resistance marker.
• Fasting glucose and HbA1c — to screen for prediabetes and type 2 diabetes.
• Oral glucose tolerance test (OGTT) — recommended in newly diagnosed PCOS, especially with BMI over 25 or family history of diabetes.
• Lipid panel (total cholesterol, LDL, HDL, triglycerides) — PCOS is associated with atherogenic dyslipidaemia.

5. Other markers commonly added

• Liver function tests (LFT) — including ALT and AST, since non-alcoholic fatty liver disease is more common in PCOS.
• Vitamin D, B12, ferritin — often suboptimal in women with PCOS and worth correcting.

Sample PCOS blood test results: what each pattern means

Here are the patterns Australian GPs and endocrinologists look for. Reference ranges are typical RCPA-aligned adult female ranges; your specific lab's range may differ slightly.

Marker	Typical PCOS pattern	What it suggests
Total testosterone	Upper-normal or elevated (often 2.5-4.5 nmol/L)	Biochemical hyperandrogenism — meets Rotterdam criterion 2.
SHBG	Low (often <30 nmol/L)	Insulin resistance suppressing SHBG; amplifies free testosterone.
Free Androgen Index (FAI)	>5	Most reliable marker of bioavailable androgen excess.
LH	Elevated, often >10 IU/L	Disordered pituitary signalling typical of PCOS.
FSH	Normal or low	Normal pituitary reserve.
LH:FSH ratio	Often >2	Classical PCOS pattern (not required for diagnosis).
AMH	Elevated, often >35 pmol/L	High follicle count consistent with polycystic ovary morphology.
Prolactin	Normal	Excludes hyperprolactinaemia as the cause.
TSH	Normal	Excludes thyroid dysfunction.
17-OH progesterone	Normal	Excludes non-classical CAH.
Fasting insulin	Often elevated (>10 mIU/L)	Insulin resistance — drives most metabolic features.
HbA1c	Normal to upper-normal	Screens for prediabetes.

Important: a "normal" sex-hormone panel does not rule out PCOS. Roughly 30% of women with PCOS have normal testosterone but display clinical hyperandrogenism (acne, hirsutism) — clinical hyperandrogenism alone meets the Rotterdam criterion. This is why blood tests must always be interpreted alongside clinical assessment and, where appropriate, ultrasound.

When in your cycle should PCOS blood tests be done?

Timing matters more than many women are told. The standard Australian recommendation:

• Day 2-5 of your cycle (where day 1 is the first day of full bleeding) — this is the early follicular phase, when LH, FSH and oestradiol are at their cycle baseline. This gives the cleanest read of pituitary signalling.
• Any time for testosterone, SHBG, FAI, AMH, prolactin, TSH, fasting insulin, glucose, HbA1c and lipids — these are not strongly cycle-dependent.
• If your cycles are absent or very irregular (oligomenorrhoea or amenorrhoea), simply have the bloods done in the morning, fasting if possible, on a day when you are not menstruating.
• If you are on hormonal contraception, talk to your GP — the pill suppresses LH, FSH, ovarian testosterone and AMH and can mask PCOS. You may need to come off the pill for 2-3 months before bloods, or rely more on clinical and ultrasound criteria.

Cost: are PCOS blood tests covered by Medicare in Australia?

Yes — most of them are. When ordered by your GP for clinical investigation of irregular cycles, hyperandrogenism or fertility concerns, the following are covered under Medicare and bulk-billed at most major Australian pathology providers (4Cyte, Laverty, Sullivan Nicolaides, Australian Clinical Labs, Dorevitch, Douglass Hanly Moir, QML):

• Total testosterone, SHBG, FAI
• LH, FSH, prolactin
• TSH
• DHEAS, 17-OH progesterone
• Fasting insulin, glucose, HbA1c, lipids, LFTs
• Pelvic ultrasound (transvaginal where appropriate)

The notable exceptions are usually AMH (typically A$60-90 out of pocket — Medicare currently restricts AMH rebates to women undergoing IVF) and any non-standard tests your GP requests outside the routine workup. Ask your pathology provider in advance — most will tell you exactly what is and is not covered before you have the blood drawn.

How to read your PCOS blood test results

Here is the framework Australian endocrinologists use:

1. Look at testosterone, SHBG and FAI together. If FAI is >5, you have biochemical hyperandrogenism — that is one of the three Rotterdam criteria ticked.
2. Check for clinical hyperandrogenism. Even if blood testosterone is normal, hirsutism, acne or scalp hair loss tick the same Rotterdam box.
3. Confirm cycle pattern. Cycles >35 days, <8 per year, or absent periods (after the first few years post-menarche) tick another Rotterdam box.
4. Rule out mimics with prolactin, TSH, 17-OH progesterone, DHEAS. If any of these are abnormal, that condition is the leading suspect — not PCOS.
5. Quantify metabolic risk with fasting insulin, glucose, HbA1c, lipids, BMI and waist circumference.
6. If 2 of 3 Rotterdam criteria are met and other causes are excluded — that is PCOS. Imaging is optional once the first 2 criteria are met.

Why blood tests alone cannot diagnose PCOS

This is the single most important point and the one most patients are not told clearly. PCOS is a clinical diagnosis made by your doctor based on the Rotterdam framework — not a single positive blood test.

• You can have PCOS with completely normal hormone bloods if you have clinical hyperandrogenism plus irregular cycles plus polycystic ovaries on ultrasound.
• You can have elevated testosterone for reasons other than PCOS — congenital adrenal hyperplasia, androgen-secreting tumours, exogenous androgens, certain medications.
• You can have polycystic-appearing ovaries on ultrasound without having PCOS — this is normal in some young women in the first few years post-menarche, and morphology alone is not sufficient.

Always interpret your bloods with your GP or specialist, not in isolation.

How often should you retest?

Once diagnosed, the standard Australian monitoring schedule is:

• Annually for the metabolic panel (fasting insulin, glucose, HbA1c, lipids, LFTs) since type 2 diabetes risk rises with age in PCOS.
• Every 2-3 years for the sex hormone panel unless symptoms or treatment change.
• Every 3 months when starting or changing treatment (metformin, oral contraceptives, anti-androgens) until stable.
• OGTT repeated every 1-3 years, especially if BMI >25 or planning pregnancy.

This is exactly the kind of pattern that BloodTrack is built to track — uploading your pathology PDFs from any major Australian lab and watching how testosterone, SHBG, FAI, fasting insulin, HbA1c and AMH evolve year-on-year tells a much richer story than any single result.

Next steps

If you suspect PCOS:

1. Book a long appointment with your GP. Ask specifically for the PCOS workup outlined above. The standard panel takes about 15 minutes to discuss properly.
2. Track your cycles for 3-6 months before your appointment if you can — irregular cycles are one of the diagnostic pillars and a written record helps.
3. Photograph any clinical signs (acne flares, hirsutism, scalp hair changes) — this gives the GP objective evidence of clinical hyperandrogenism.
4. Have the bloods drawn day 2-5 of your cycle if possible, fasting, in the morning.
5. Save and track every result over time — PCOS is a long-term condition and the trajectory of your hormones and metabolic markers matters as much as any single reading.

For deeper context on each individual marker, see our glossary entries for testosterone, SHBG, TSH, ferritin, ALT and the full blood marker glossary. For an in-depth, condition-specific dashboard, see our PCOS condition guide.

Medical disclaimer: This article is for educational purposes only and is not medical advice. PCOS is a clinical diagnosis that should be made by your GP or specialist based on your full medical history, examination and investigations. Always discuss your blood test results with a qualified healthcare professional.