Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting young women, and about 10% of all reproductive age women. It affects mood, nutrition, gut health, skin health, fertility and menstrual cycles. When it advances women are at risk for diabetes and heart disease. Diagnosing PCOS requires lab tests to assess hormone imbalances, metabolic health, and other underlying factors. These tests not only confirm PCOS but also guide treatment.
Why Lab Tests Matter in PCOS
Diagnosed based on the Rotterdam Criteria, which require at least two out of three of the following:
✔ Irregular or absent periods (Ovulatory Dysfunction)
✔ Elevated androgens (male hormones) (Clinical or Lab Evidence)
✔ Polycystic ovaries on ultrasound
Rotterdam consensus also described 4 body types for PCOS: A: which is the most severe, those who don’t ovulate, have cystic ovaries , and elevated hormones, B: those who don’t ovulate and have elevated male hormones, C: those with cystic ovaries and elevated male hormones and actually do ovulate D: those who don’t ovulate, and have cystic ovaries. Lab tests help confirm the type and how severe. Lab tests rule out other causes of irregular cycles, and assess associated metabolic risks like insulin resistance and cardiovascular disease.
Essential Lab Tests for PCOS Diagnosis
1. Hormone Panel
✔ Testosterone (Total & Free) – Elevated levels indicate androgen excess, leading to acne, hair thinning, and excess facial/body hair.
✔ DHEA-S (Dehydroepiandrosterone sulfate) – A precursor to testosterone produced by the adrenal glands. Helps distinguish ovarian vs. adrenal causes of PCOS symptoms.✔ LH (Luteinizing Hormone) & FSH (Follicle-Stimulating Hormone) – PCOS often shows a high LH-to-FSH ratio (>2:1), indicating ovulation dysfunction.
✔ Estradiol (E2) – Often normal or slightly elevated, reflecting estrogen dominance in PCOS.
✔ Prolactin – Elevated prolactin levels can mimic PCOS symptoms but may indicate prolactinoma (a benign pituitary tumor) instead.
LH and FSH testing help to figure out ovulatory disfunction.
2. Metabolic & Insulin Resistance Tests
✔ Fasting Insulin & Glucose – High fasting insulin suggests insulin resistance, a key driver of PCOS symptoms and weight gain.
✔ HOMA-IR (Homeostatic Model Assessment for Insulin Resistance) – Calculates insulin resistance and is more reliable than fasting glucose alone.
✔ Hemoglobin A1c (HbA1c) – Measures long-term blood sugar control and screens for prediabetes and Type 2 diabetes.
✔ Lipid Panel (Cholesterol, Triglycerides, LDL, HDL) – PCOS increases the risk of heart disease due to high triglycerides and low HDL (“good” cholesterol).
3. Thyroid & Other Rule-Out Tests
✔ TSH (Thyroid-Stimulating Hormone) – Hypothyroidism can mimic PCOS symptoms like weight gain, irregular cycles, and hair loss. In pure PCOS these are normal.
✔ Free T3 & Free T4 – Measures active thyroid hormone levels.
✔ Thyroid Antibodies (TPO, TG Antibodies) – Screens for Hashimoto’s thyroiditis, which can contribute to cycle irregularities.
✔ 17-Hydroxyprogesterone (17-OHP) – Rules out congenital adrenal hyperplasia (CAH), and non-classicla adrenal hyperplaisa which is due to 21-hydroxylase deficiency, both conditions that mimic PCOS. Generally normal or mildly elevated in PCOS.
Androstenedione a precursor to testosterone and estrone, produced by the adrenal glands and ovaries. And we sometimes use this to determine if the elevated androgens are adrenal or ovarian
Advanced PCOS Tests for a Deeper Look
✔ SHBG (Sex Hormone-Binding Globulin) – PCOS often leads to low SHBG, increasing free testosterone and worsening androgen symptoms. This is an often overlooked test which we will order for you.
✔ AMH (Anti-Müllerian Hormone) – Elevated in PCOS, reflecting increased ovarian follicle count, though not part of formal diagnosis. Newest research says the more elevated the AMH the worse the PCOS and the less likely a woman is to being fertile. Not a test we use in teens. It also is interpreted in a range, and over time. Chinese women have lower AMH levels naturally than Europeans.
✔ Cortisol & ACTH (Adrenal Testing) – Assesses chronic stress and rules out Cushing’s Syndrome, which can mimic PCOS symptoms.
Interpreting Your Lab Results
Generally speaking, there is a lot to discuss, a lot to monitor, and we want to help you understand whether you are fertile, nearing menopause, or have medical issues to attend to. Lowering stress and total body inflammation is very important as well. Individuals tested as teens require retesting in their early 20s to make sure the information was accurate as your body matured.
🚨 High Androgens + Irregular Cycles? Likely PCOS
🚨 Normal Testosterone and DHEA-S but Irregular Cycles? May indicate thyroid or hypothalamic dysfunction
🚨 Elevated Insulin + Weight Gain? Insulin-resistant PCOS, often responds to lifestyle changes & medications like metformin or GLP-1s
Next Steps After PCOS Testing
1️⃣ Lifestyle Modifications – Low-glycemic diets, strength training, and stress reduction improve insulin resistance.
2️⃣ Medical Management – Based on labs, doctors may recommend metformin, GLP-1s, spironolactone, or birth control pills. For some testosterone pellets can help the levels normalize and normalize your SHBG.
3️⃣ Regular Monitoring – Lab tests should be repeated every 6-12 months to track hormone and metabolic health.
Final Thoughts
Lab testing for PCOS provides crucial insights into hormonal imbalances, metabolic risks,future pregnancy plans, and personalized treatment options. Whether you suspect PCOS or need guidance on managing it, testing is the first step toward understanding your health and optimizing your well-being.
📍 Need PCOS testing? Contact us Women’s Health Practice 217-356-3736 for a consultation.
