A 28-year-old woman with irregular periods and hirsutism is found to have elevated androgen levels and polycystic ovaries on ultrasound. Which single feature best distinguishes PCOD (PCOS) from idiopathic hirsutism?

Explanation

## Distinguishing PCOD from Idiopathic Hirsutism **Key Point:** PCOD (PCOS) is a syndrome defined by the Rotterdam criteria, requiring at least 2 of 3 features: ovulatory dysfunction (irregular cycles), clinical/biochemical hyperandrogenism, and polycystic ovarian morphology on ultrasound. Idiopathic hirsutism is isolated androgen-dependent hair growth without systemic dysfunction. ### Comparison Table | Feature | PCOD (PCOS) | Idiopathic Hirsutism | | --- | --- | --- | | **Menstrual cycles** | Irregular/anovulatory | Regular, ovulatory | | **Androgen levels** | Elevated (free T, androstenedione) | Normal or borderline | | **Ovarian morphology** | Polycystic (>12 follicles, ↑ stroma) | Normal | | **Metabolic features** | Insulin resistance, dyslipidemia | Absent | | **Fertility** | Often impaired | Normal | **High-Yield:** The combination of **ovulatory dysfunction + hyperandrogenism + polycystic ovaries** is pathognomonic for PCOD. Idiopathic hirsutism has none of these systemic features—it is a cosmetic problem with normal hormones, cycles, and ovaries. **Clinical Pearl:** A woman with hirsutism alone (normal cycles, normal androgens, normal ultrasound) does not have PCOD; she has idiopathic hirsutism and requires only cosmetic or antiandrogen therapy, not metabolic workup. **Warning:** Do not confuse elevated DHEA-S (which suggests adrenal androgen excess or adrenal tumour) with PCOD. DHEA-S is typically normal in PCOD; elevated free testosterone and androstenedione are the hallmark.