In 1999, the first legal sex change operations were conducted in Japan. The fact that there were several hundred people waiting to undergo such treatments suggested that, for some individuals, the tensions between psychic identity, social expectations, cultural constructions of masculinity and femininity, and legal definitions of maleness and femaleness (as defined through biological characteristics) were too much to bear. For these individuals – some seeking to transform male bodies into female bodies, some seeking to transform female bodies into male bodies – only a gruelling physical transformation could resolve these tensions.

For these individuals, however, the possibility of undertaking such radical treatment was determined by government legislation and the closely regulated practices of the medical profession. From the earliest days of modern Japan, governments had regulated individual bodies, limiting choices about reproduction, contraception, surgical abortion, and sterilisation procedures. In revision of the Eugenic Protection Act in 1996, some of the controls on sterilisation procedures had been relaxed. In a possibly unforeseen consequence, the restrictions on sex change operations were also removed. Such operations, which involve the modification of healthy reproductive organs, had been interpreted as a form of sterilisation, an operation which was only recognised for eugenic purposes. With the modification of regulations on sterilisation, sex change operations were recognised for the first time and started to be carried out once hospitals could set up the necessary counselling and training in gender appropriate behaviour for those undergoing this surgical treatment, and once the necessary ethical clearances had been obtained.