Endocrine Abstracts

Background: Persistent vaginal bleeding can be psychologically stressful and incongruent with gender identity in transgender men (assigned female at birth with male gender identity). Previous studieshave cross-sectionally described amenorrhea in cohorts of transgender men on intramuscular or subcutaneous testosterone injections. It remains uncertain which testosterone preparations most effectively suppress vaginal bleeding and when amenorrhea occurs after testosterone initiation. This study investigates the clinical effects of various testosterone preparations on vaginal bleeding and spotting in transgender men.

Methods: This prospective cohort study was part of the European Network for the Investigation of Gender Incongruence (ENIGI). Data on the persistence (yes/no) and intensity (continuous scale) of vaginal bleeding and spotting, serum sex steroid levels and body composition were prospectively and cross-sectionally assessed in 267 transgender men during a three-year follow-up period, starting at the initiation of various testosterone preparations. Testosterone therapy was aimed at male serum testosterone levels.

Results: After three months of testosterone, 17.9% of transgender men reported persistent vaginal bleeding and 26.8% reported spotting. The percentages reporting vaginal bleeding and spotting decreased over the first year of testosterone (bleeding 4.7% and spotting 6.9% at 12 months, respectively), with no participants reporting vaginal bleeding or spotting after 18 months of testosterone.

Factors associated with vaginal bleeding or spotting included lower serum testosterone levels and being on testosterone gel, as compared to injections (e.g., esters or undecanoate preparations). If vaginal bleeding persisted, starting progestogens at three months resulted in a decrease in the intensity of vaginal bleeding and spotting.

Discussion: Testosterone therapy aimed at male physiologic ranges will result in cessation of vaginal bleeding and spotting in the majority of transgender men within three months. If not, serum testosterone levels should be measured and testosterone dose adjusted to achieve serum testosterone levels in the physiologic male range. Adding a progestin can be considered after three to six months if bleeding persists. Providers should be aware that cessation of bleeding can be more difficult to achieve in transgender men with lower serum testosterone levels or those on testosterone gel.