PCOS Blood Tests: The Labs Worth Asking About
Labs · Testing · Updated 2026-07-20
PCOS is diagnosed and managed with data, and most of that data comes from blood work. Yet many people leave appointments with only a glucose test - while the labs that actually explain symptoms, like fasting insulin or SHBG, were never ordered.
Here are the panels commonly used in PCOS care, what each one shows, and the ones worth asking about by name. Your clinician decides what fits your case - this list is for the conversation, not a substitute for it.
The commonly ordered panels
| Lab | What it shows |
|---|---|
| Total & free testosterone | Androgen level - elevated in many with PCOS; drives acne, hirsutism, hair loss |
| SHBG | The protein that binds testosterone; low SHBG raises the free, active fraction |
| Free Androgen Index | Calculated from testosterone and SHBG when free T is not measured directly |
| DHEA-S | The adrenal androgen - helps show where excess androgens come from |
| Fasting insulin + glucose | Together they give HOMA-IR, the early insulin-resistance signal |
| HbA1c | Three-month average blood sugar; screens for prediabetes |
| Lipid panel | Triglycerides and cholesterol - metabolic risk that PCOS raises |
| AMH | Follicle count signal, typically high in PCOS |
| TSH / thyroid | Rules out thyroid causes of irregular cycles |
| Prolactin | Rules out another common cause of missed periods |
Timing and units matter
- Hormones like testosterone are often drawn in the morning, and cycle timing can matter for some labs - follow the draw instructions you are given.
- Labs report in different units and reference ranges; always compare a result to the range printed next to it.
- Keep every result - a single value says little, but the same marker over two years tells a story.
All 20 markers, one record. PCOS Diet & Symptom Tracker keeps testosterone, SHBG, DHEA-S, HOMA-IR, HbA1c, AMH, thyroid and more with reference bands and trend charts - and exports a doctor-visit PDF so your history walks into every appointment with you. Learn more about PCOS Diet & Symptom Tracker.
Bringing it to your appointment
A tracked lab history changes the conversation: instead of one number, your clinician sees direction. Pair it with a prepared appointment plan and the visit gets dramatically more useful. Educational content only - testing decisions belong with your clinician.
Frequently asked questions
What tests confirm PCOS?
There is no single test. Diagnosis typically combines cycle history, signs or labs of elevated androgens, and ultrasound findings, while ruling out thyroid, prolactin, and other causes.
Should I fast before PCOS blood work?
For insulin, glucose, and lipids - yes, usually 8-12 hours. Follow the instructions from your lab or clinician.
How often should PCOS labs be repeated?
Many care teams re-check key labs every 6-12 months, or a few months after a treatment change. Your clinician sets the schedule.
Why track labs myself if the clinic has them?
Results scatter across portals and clinics, and trends get lost. Your own record keeps every marker, every draw, in one place you control.