Clinical diagnosis of hirsutism

The Ferriman-Gallwey score can be used to diagnose and assess the severity of hirsutism; an online tool is available from the Endocrine Society. Thresholds used to define hirsutism vary among ethnic groups.

Ask about the distribution of excess hair to distinguish hirsutism from hypertrichosis. Establish the timeframe in which it has developed; rapid onset is suggestive of adrenal or ovarian tumours.

Ask about features of PCOS, particularly menstrual disturbance, and exclude exposure to exogenous steroids, topical testosterone or oral sodium valproate therapy. Also examine for signs of PCOS, such as obesity or acne.

Assess all females with hirsutism (or with a combination of localised excess hair and abnormal menstrual patterns), regardless of severity, for an underlying cause; the likelihood of elevated serum androgen concentrations cannot be predicted by severity of hirsutism.

Note: Assess all females with hirsutism for an underlying cause.

Imaging and specialist referral are required if any features suggestive of an androgen-secreting tumour (ovarian or adrenal) are present, such as:

rapid onset of hirsutism
onset of hirsutism in a postmenopausal female
virilising features such as clitoromegaly, voice deepening, development of muscular body habitus or breast atrophy.

Also consider whether hirsutism is a feature of:

Cushing syndrome, which may cause central obesity, facial puffiness, peripheral oedema and skin thinning
nonclassical congenital adrenal hyperplasia, which can be clinically indistinguishable from PCOS; it may be differentiated on laboratory investigations.