Background: No data are available at present on the prevalence of gender dysphoria (trans-identity) in Germany. On the basis of estimates from the Netherlands, it can be calculated that approximately 15 000 to 25 000 persons in Germany are affected. Persons suffering from gender dysphoria often experience significant distress and have a strong desire for gender reassignment treatment.
Methods: This review is based on pertinent publications retrieved by a selective search in the PubMed database employing the searching terms "transsexualism," "transgender," "gender incongruence," "gender identity disorder," "gender-affirming hormone therapy," and "gender dysphoria."
Results: In view of its far-reaching consequences, some of which are irreversible, hormonal gender reassignment treatment should only be initiated after meticulous individual consideration, with the approval of the treating psychiatrist/psychotherapist and after extensive information of the patient by an experienced endo - crinologist. Before the treatment is begun, the patient must be extensively screened for risk factors. The contraindications include severe preexisting thromboembolic diseases (mainly if untreated), hormone-sensitive tumors, and uncontrolled pre - existing chronic diseases such as arterial hypertension and epilepsy. Finding an appropriate individual solution is the main objective even if contraindications are present. Male-to-female treatment is carried out with 17β-estradiol or 17β-estradiol valerate in combination with cyproterone acetate or spironolactone as an antiandrogen, female-to-male treatment with transdermal or intramuscular testosterone preparations. The treatment must be monitored permanently with clinical and laboratory follow-up as well as with gynecological and urological early-detection screening studies. Prospective studies and a meta-analysis (based on low-level evidence) have documented an improvement in the quality of life after gender reassignment treatment. Female-to-male gender-incongruent persons often have difficulty being accepted in a gynecological practice as a male patient.
Concluzion: Further prospective studies for the quantification of the risks and benefits of hormonal treatment would be desirable. Potential interactions of the hormone preparations with other medications must always be considered.