Salivary testosterone concentrations were measured in male and female members of four heterosexual couples on a total of 11 evenings before and after sexual intercourse and 11 evenings on which there was no intercourse. Testosterone increased across the evening when there was intercourse and decreased when there was none. The pattern was the same for males and females. Early evening measured did not differ on the two kinds of days, suggesting that sexual activity affects testosterone more than initial testosterone affects sexual activity.
Hypoactive sexual desire disorder (HSDD) is a deficiency of sexual desire that causes marked personal or interpersonal distress. It occurs in approximately 1 in 10 adult women. A number of potential contributory factors (hormonal, neurobiological and psychosocial) have been identified. Testosterone plays an excitatory role in sexual desire but the mechanism is not yet well understood. Treatment with testosterone has been shown to improve sexual desire in menopausal women with HSDD. However, there are limited data concerning premenopausal women and long-term safety. At present, physiological testosterone preparations for use in women are not available in Switzerland.
Dihydrotestosterone (DHT) (referred to as androstanolone or stanolone when used medically) can also be used in place of testosterone as an androgen. The availability of DHT is limited; it is not available in the United States or Canada, for instance, but it is available in certain European countries, including the United Kingdom , France , Spain , Belgium , Italy , and Luxembourg .  DHT is available in formulations including topical gel, buccal or sublingual tablets, and as esters in oil for intramuscular injection.  Relative to testosterone, and similarly to many synthetic AAS, DHT has the potential advantages of not being locally potentiated in so-called androgenic tissues that express 5α-reductase (as DHT is already 5α-reduced) and of not being aromatized into an estrogen (it is not a substrate for aromatase).