Background: Adding testosterone to hormonal therapy could improve sexual function and general well-being among women during climacteric. We evaluated the effectiveness of testosterone undecanoate on sexual function in postmenopausal women utilizing the standardized questionnaire FSFI score.

Methods: Postmenopausal women with sexual complaints and Female Sexual Function Index (FSFI) ≤ 26.5 were enrolled in to this randomized, double-blinded, placebo-controlled trial. Participants were randomly assigned to 8-week treatment with either oral testosterone undecanoate 40 mg or placebo twice weekly with daily oral estrogen. The FSFI scores before and after treatment were compared to assess any improvement of sexual function.

Results: Seventy women were recruited of which each group had 35 participants. The baseline characteristics and baseline FSFI scores were comparable between both groups. After 8 weeks of treatment, the FSFI scores significantly improved in both groups when compared to the baseline but the FSFI scores from the testosterone group were significantly higher than in the placebo group post-treatment (28.6 ± 3.6, 25.3 ± 6.7, respectively, p = 0.04). There was no difference in adverse effect between the two groups

Conclusions: The twice weekly addition of testosterone undecanoate to daily oral estrogen was associated with a significant improvement in sexual function among postmenopausal women than the use of the estrogen alone.