Should genitourinary medicine clinic attendees with sexual dysfunctions have routine assessment of testosterone levels?

Background Many genitourinary medicine departments see patients with sexual dysfunction. The use of routine testosterone assays in men complaining of erectile dysfunction is commonplace. Some departments also carry out screening of women complaining of loss of libido.
Methods A search of the literature was undertaken to assess the evidence for usefulness of testosterone assay in males complaining of erectile dysfunction and women with low sex drive or arousal problems. The optimal assay was similarly assessed.
Results and discussion There is no place for the routine assay of serum testosterone levels in men with erectile dysfunction unless they complain of low sexual desire, or there are grounds for suspecting that they are clinically hypogonadal. In women who complain of low sexual desire or arousal, serum testosterone levels need to be assayed only if there is a history of oöphorectomy of cytotoxic therapy, or other reasons for suspecting endocrine abnormalities. Where the vulva might be deemed hypoplastic, the level of 5 alpha dihydrotestosterone might be low. Where possible, free or bioavilable testosterone levels rather than total testosterone should be measured as these provide a more sensitive and specific indication of the true androgen level. The ration of total testosterone to sex hormone binding gives the `free testosterone index', which may also be used. The additional costs to these procedures are grounds for limiting their use to situations where they are likely to prove of real benefit in undertaking treatment.