Testosterone improves libido in female estrogen diminishes

Abstract
OBJECTIVE:
To describe sexual desire in female-to-male transsexual persons post sex reassignment surgery (SRS). The associations between serum androgen levels and sexual desire are examined.

DESIGN:
Single center cross-sectional study.

METHODS:
Forty-five female-to-male transsexual persons post SRS completed a standardized questionnaire assessing sexual desire (Sexual Desire Inventory). In addition, participants were asked questions on sexual desire before starting hormone treatment and having SRS. Serum levels of testosterone, LH and sex hormone-binding globulin were measured on fasting morning serum samples.

RESULTS:
In retrospect, 73.9% of the participants reported an increase in sexual desire after hormone treatment and SRS. Solitary sexual desire scores were significantly correlated with frequency of masturbation (r=0.835; P<0.001), whereas frequency of sexual intercourse with a partner was not. No direct associations were found between testosterone and solitary or dyadic sexual desire. However, ANOVA showed an independent effect of LH on solitary sexual desire (P<0.001). Post hoc analysis revealed that female-to-male transsexual persons with elevated levels of LH, indicating suboptimal testosterone therapy, reported significantly lower solitary sexual desire levels (than those with low LH levels; P=0.007). Suppressed LH levels were also associated with having a higher need for sexual activities (P=0.009) and a higher frequency of excessive sexual desire (P=0.007).

CONCLUSION:
Most female-to-male transsexual persons report on a marked increase in sexual desire after testosterone treatment and SRS. No direct associations between levels of testosterone and solitary or dyadic sexual desire were found. However, measures of sexual desire were inversely associated with LH levels.