Iris de Nie

90 C H A P T E R 6 Figure 1 . Study flowchart Characteristics at time of gGAS are presented in Table 1. Mean age at gGAS was 29.6 years (SD 12.4) and was lower in people who started medical treatment in adolescence compared to those who started medical treatment in adulthood. Since adolescents started medical treatment with puberty suppressive therapy and had to wait until reaching the age of 18 years before being able to undergo gGAS, prior medical treatment duration was longer in the adolescent subgroups compared to those who initiated treatment at adult age. Different estradiol formulations were prescribed, including estradiol patches (50-150 µg/24 hours twice weekly), estradiol gel (0.75-3.0 mg daily) and oral estradiol valerate or hemihydrate (2-6 mg daily). Testosterone suppressing therapy consisted of triptorelin injections (3.75 mg i.m./s.c. every 4 weeks or 11.25 mg i.m. every 12 weeks) for those who initiated treatment as adolescent, and cyproterone acetate (25-100 mg daily) for those who initiated treatment as adult. The last known serum hormone levels, median 189 days (IQR 96-340) before gGAS, showed that testosterone was adequately suppressed (median 0.7 nmol/L, IQR 0.5-1.0) and estradiol levels were in the female range (median 193 pmol/L, IQR 120-307). Furthermore, LH and FSH levels were suppressed. In transgender women with a cessation of GAHT 4 weeks prior to gGAS, estradiol levels were lower, and testosterone and LH levels were higher, compared to those who continued GAHT until gGAS.