Davis SR et al. for the APHRODITE Study Team (2008) Testosterone for low libido in postmenopausal women not taking estrogen. N Engl J Med 359: 2005–2017

Transdermal exogenous testosterone improves libido in postmenopausal women receiving estrogen therapy. Davis et al. have now demonstrated that 300 µg of testosterone a day, administered via skin patches, results in a modest but clinically important increase in sexual function in postmenopausal women with hypoactive sexual desire disorder who are not receiving estrogen.

This multicenter, double-blind study enrolled 814 women who had undergone menopause at least 12 months before enrollment and who had hypoactive sexual desire disorder. Women were randomly assigned to receive two placebo patches, one placebo patch and one 150 µg testosterone patch, or two 150 µg testosterone patches, daily for 52 weeks.

At week 24, the increase from baseline in the 4-week frequency of satisfying sexual episodes was significantly greater in women receiving 300 µg testosterone than in patients receiving placebo (mean 2.1 episodes vs 0.7 episodes; P <0.001). Compared with the placebo group, both testosterone therapy groups had a significant increase in sexual desire and a significant decrease in personal distress at week 24. The incidence of adverse effects throughout the study period was similar in all three groups, although there was a higher incidence of androgenic adverse effects, particularly increased hair growth, in women receiving 300 µg testosterone. Four patients were diagnosed with breast cancer during the first 4 months of the study, one of whom had symptoms before randomization.

These findings indicate that concurrent exogenous estrogen is not required to ensure the efficacy of exogenous testosterone for hypoactive sexual desire disorder.