Time course of effects of testosterone administration on sexual arousal in women

Background: The assumption that testosterone is involved in human female sexual functioning is mainly based on results of studies of women with hypogonadotropic hypogonadism This study sought to determine the effect of testosterone administration on physiological and subjective sexual arousal in sexually functional women. Methods: In a double-masked, randomly assigned, placebo-controlled crossover design, we examined whether administration of a single dose of testosterone to sexually functional women increases vaginal and subjective sexual arousal when they are exposed to erotic visual stimuli. To search for a time lag in the effect of testosterone therapy, we exposed 8 healthy women to 6 erotic film excerpts depicting intercourse. The first and second excerpts were shown immediately before and 15 minutes after, respectively, intake of placebo or testosterone; the last 4 excerpts were then shown at 11/2-hour intervals. Results: Sublingual intake of testosterone caused a sharp increase in plasma testosterone levels within 15 minutes; these levels declined to baseline values within 90 minutes. Three to 41/2 hours after reaching peak testosterone level, we found a statistically significantly increase in genital responsiveness (P =.04). Furthermore, on the day of testosterone treatment, there also was a strong and statistically significant association between the increase in genital arousal and subjective reports of "genital sensations" (P =.02) and "sexual lust" (P =.01) after 41/2 hours. Conclusions: There is a time lag in the effect of sublingually administered testosterone on genital arousal in women. In addition, a consecutive increase in vaginal arousal might cause higher genital sensations and sexual lust.