• female-to-male;
  • gender identity disorder;
  • male-to-female;
  • sex reassignment surgery


An incongruence between one's physiological sex and the gender identity that is one's basic sense of self as a man or a woman is known as gender identity disorder. In general, the conditions of physiological men having female gender identity and physiological women having male gender identity are called male-to-female and female-to-male gender identity disorder, respectively. Although the precise pathogenesis of gender identity disorder remains unclear, the prevalence of gender identity disorder is quite high, with the rates calculated for male-to-female to be 1:25 000 and female-to-male to be 1:12 000 in Hokkaido, Japan. The diagnosis and treatment of gender identity disorder in Japan are based on the Diagnostic and Therapeutic Guidelines for Patients with Gender Identity Disorder, 4th edition. Although gender identity disorder was previously thought to be a psychiatric condition, it is extremely difficult to assign gender identity to physiological sex by psychiatric and psychological treatments. To adapt the figure of the body to the native gender identity, physical treatments such as administration of cross-sex steroids and sex reassignment surgery are considered. However, there are very few institutions that routinely carry out sex reassignment surgery in Japan, even though it is mandatory for changing sex on the census register at the present time. Sex reassignment surgery for male-to-female and female-to-male patients includes orchiectomy, penectomy, clitoroplasty, vaginoplasty and vulvoplasty, and hysterectomy, ovariectomy, metoidioplasty and phalloplasty, respectively. To provide accurate information about physical treatment for patients with gender identity disorder, even urologists who are not actively involved in the diagnosis and treatment of gender identity disorder should understand the fundamental aspects and contemporary problems of gender identity disorder.