Facial Hair Growth

Facial hair growth in women becomes a clinical concern when it follows a male pattern — coarse, dark hair on the chin, upper lip, jawline and neck — a pattern termed hirsutism. The distinction from fine, light vellus hair matters, because hirsutism signals androgen activity at the follicle. In around 70-80% of cases the driver is polycystic ovary syndrome. In others, circulating androgens are normal but the follicles are genetically more sensitive to them, which is why hirsutism clusters in families and varies by ethnicity. Less commonly the cause is an androgen-secreting source that needs exclusion: congenital adrenal hyperplasia, Cushing syndrome or, rarely, an androgen-producing tumour, which is why rapid onset over months rather than years is a red flag. Certain medications including some progestins, danazol and anabolic agents drive it directly. Treatment works on two tracks: cosmetic removal for existing hair, and hormonal therapy — usually combined oral contraception, with anti-androgens added where needed — to slow new growth. Existing hairs do not respond to hormone therapy and require removal, which is why expectations should be set at months, not weeks.

• •Coarse dark hair on the chin, upper lip, jawline, neck or chest
• •Gradual onset from late teens or twenties in PCOS
• •Irregular or infrequent periods suggesting PCOS
• •Acne and scalp hair thinning accompanying the pattern
• •Rapid progression over months, virilisation or voice change — red flags for androgen-secreting pathology
• •Central weight gain and skin tags suggesting insulin resistance

• •Polycystic ovary syndrome — the cause in 70-80% of cases
• •Idiopathic follicle sensitivity to normal androgen levels
• •Insulin resistance amplifying ovarian androgen production
• •Non-classic congenital adrenal hyperplasia
• •Medications: some progestins, danazol, anabolic steroids, ciclosporin
• •Cushing syndrome
• •Androgen-secreting ovarian or adrenal tumours, rare but defined by rapid onset
• •Menopause-related androgen-to-oestrogen shift

Hair follicles in androgen-sensitive areas convert weak androgens to dihydrotestosterone via 5-alpha-reductase, transforming fine vellus hairs into coarse terminal hairs. In PCOS, elevated ovarian androgen production drives this directly. In idiopathic hirsutism, normal androgen levels meet genetically hypersensitive follicles. Insulin resistance amplifies ovarian androgen output, linking the condition to metabolic health.