The diagnostic toolkit modern PCOS care actually uses
Modern PCOS care uses a structured set of labs, imaging and screening scales to confirm the diagnosis, classify your phenotype, rule out look-alike conditions and map long-term risk. Here is what each part of the toolkit does.
1. Diagnosis: the Rotterdam criteria
PCOS is diagnosed when 2 of 3 features are present: (1) irregular or absent ovulation, (2) clinical or biochemical hyperandrogenism, and (3) polycystic ovaries on ultrasound. Other causes of the same symptoms (thyroid disease, high prolactin, non-classic adrenal hyperplasia) are excluded first. In adults, irregular cycles plus hyperandrogenism are enough for diagnosis without an ultrasound. The combination you have decides your phenotype (A, B, C or D).
2. Clinical assessment
- Cycle history: number of periods in the past 12 months, cycle length, flow
- Height, weight, BMI and waist circumference (Asian cut-offs: overweight from BMI 23, obese from BMI 25; waist over 80 cm for women)
- Blood pressure
- Modified Ferriman-Gallwey (mFG) score across 9 body areas, each rated 0-4. A score of 8 or more indicates hirsutism in South Asian women
- Acne, scalp hair thinning, and dark velvety skin patches (acanthosis nigricans)
3. Blood tests
Hormonal and exclusion tests: Total testosterone with SHBG (to calculate free androgen index) or free testosterone, DHEAS, LH and FSH, TSH, prolactin, and 17-hydroxyprogesterone to exclude non-classic adrenal hyperplasia. AMH may be used in adults as an alternative to ultrasound when only one of the two main criteria is present.
Metabolic tests: Fasting glucose and a 75 g oral glucose tolerance test (OGTT) or HbA1c, fasting insulin for HOMA-IR, lipid profile, liver function tests, vitamin D, and vitamin B12 for those on long-term metformin.
HOMA-IR: HOMA-IR = (fasting insulin x fasting glucose) / 405, using insulin in uIU/mL and glucose in mg/dL. A value above 2.5 suggests insulin resistance.
4. Pelvic ultrasound
A transvaginal ultrasound looks at ovarian volume and follicle count. Under the 2023 guideline, polycystic ovarian morphology is 20 or more follicles per ovary or an ovarian volume of 10 mL or more, measured with a high-frequency probe. Ultrasound is not advised for diagnosis in the first 8 years after the first period. A transabdominal scan can be used if a transvaginal scan is not appropriate. Ultrasound also checks the endometrial lining when cycles are very infrequent.
5. Screening scales and self-checks
- Rotterdam PCOS self-check: estimates whether you likely meet the menstrual and androgen criteria
- mFG hirsutism score: the standard clinical scale for unwanted terminal hair
- PHQ-9: depression screening; PCOS raises depression risk 3-4 times
- PCOS symptom questionnaire: covers reproductive, metabolic, skin and mood symptoms
- BMI + waist risk calculator and HOMA-IR calculator
6. Mental health, sleep and lifestyle screening
A complete PCOS work-up also screens for anxiety and depression, sleep problems (STOP-BANG for sleep apnea), eating patterns and body image concerns, physical activity, and smoking and alcohol use.
7. Follow-up monitoring
- Yearly: glucose (HbA1c or OGTT), blood pressure, lipids, weight and waist
- Liver tests yearly; liver ultrasound or FibroScan if ALT is raised
- B12 yearly if on metformin for more than 5 years; potassium checks if on spironolactone
- Review of cycle pattern and endometrial protection at every visit
Tests can be done through a NABL-accredited home blood draw, with results reviewed in a video consultation with a gynecologist or endocrinologist.
