Physical and Psychological Effects of Gender-Affirming Hormonal Treatment Using Intramuscular Testosterone Enanthate in Japanese Transgender Men

Abstract

Introduction The evidence on gender-affirming hormonal treatment (HT) for transgender persons is still insufficient. Aim To characterize the physical and psychological effects of HT using testosterone enanthate in transgender men, and to validate the safety of this treatment. Methods A total of 85 Japanese transgender men who were followed up for at least 1 year at our gender clinic from 2004 to 2017 were included in this study. All self-reported effects that they recognized and regularly acquired laboratory data were investigated after initiation of HT. Main Outcome Measure HT mainly using testosterone enanthate 250 mg every 2 weeks caused the most desired physical effects to appear promptly and effectively, whereas small but not negligible numbers of undesired physical and psychological effects were also confirmed. Results The initial dose of testosterone enanthate was 250 mg for 72 (84.7%) subjects, and the injection interval was maintained every 2 weeks for 70 (82.3%). Most physical effects appeared within 6 months. A deepened voice (87.1%), cessation of menses (78.8%), acne (69.4%), and facial (52.9%)/body (37.6%) hair growth occurred within 3 months. Although recognition of psychological effects was rare, emotional instability (9.4%) and increased libido (7.1%) appeared in the relatively early phase after beginning HT. The mean values for red blood cells, hemoglobin, uric acid, and alkaline phosphatase were significantly increased for 2 year. During the observation period, there were no life-threatening adverse effects in any subjects. Conclusion The present HT strategy is effective and safe for Japanese transgender men. The information from self-reported effects and objective data from blood tests can help both physicians and transgender men to understand testosterone HT. Kirisawa T, Ichihara K, Sakai Y, et al. Physical and Psychological Effects of Gender-Affirming Hormonal Treatment Using Intramuscular Testosterone Enanthate in Japanese Transgender Men. Sex Med 2021;9:100306.

Effects of testosterone treatment on transgender males: A single-institution study

“…20 Two studies from Japan demonstrated the same concept of increased uric acid with testosterone therapy in TM. 10,21 This effect was dose dependent. Several mechanisms have been proposed.…”

“…A very recent study from Japan demonstrated a 1-year efficacy and safety of intramuscular testosterone enanthate (250 mg intramuscular every 2 weeks) in TM. 10 Another Japanese study proved the dose-dependent masculinizing efficacy from variable doses of intramuscular testosterone enanthate (250 mg every 2 weeks, 250 mg every 3 weeks, and 125 mg every 2 weeks) with no significant side effects. 11 This study confirms the masculinizing effect of testosterone therapy on TM.…”

Dermatologic Care of Hair in Transgender Patients: A Systematic Review of Literature

“…Masculinizing hormone therapy commonly relies on testosterone to inhibit estrogen and exert robust masculinizing effects. Testosterone has a significant effect on both facial hair growth and body hair growth, which has been reported in 53-100% and 34-100% of patients, respectively [9,21,35]. Increased facial hair growth can be noted within 1-6 months [7].…”

Southern African HIV Clinicians Society gender-affirming healthcare guideline for South Africa

“…66 In a client taking masculinising HT, an increase in sexual desire and activity is often reported 66 , and clitoral enlargement is likely to occur. 67 Vaginal atrophy may occur because of the hypoestrogenic effect that testosterone has on vaginal tissues 68 and can be ameliorated with lubricants.…”

“…Oral testosterone should be avoided as it is hepatotoxic. 67 A client with severe hypertension, sleep apnoea or untreated polycythaemia (haematocrit above 55%) requires management prior to treatment initiation, as these conditions may be exacerbated by testosterone. 66 Testosterone treatment options are shown in Table 7 66,129 , whilst effects and reversibility of treatment are shown in Table 8.…”