Photo/IllutrationThe transgender woman, left, and her lawyer hold a news conference after she filed a request for a change in the sex of her family register at the Kyoto Family Court in Kyoto on Feb. 8. (Hiroki Okitsu)

KYOTO--A married transgender woman, who was born a male and underwent sex change surgery, asked a court here on Feb. 8 to allow her to change her sex in her family register.

If approved, the step could pave the way for recognizing same-sex marriages in Japan.

The woman, who is in her 50s and runs a company, argued in the case filed at the Kyoto Family Court that her constitutional right to pursue happiness was being violated by the law on special cases in handling gender status for people with gender identify disorder.

She contended since the law contains a clause that does not allow married people to change the sex in their family register, she would have to get a divorce to do so.

“Why am I being forced to choose between happiness living as a woman and happiness living with my family?” she said at a news conference after filing the request. “I would like the public to realize the disparity between the law and the Constitution.”

Kazuyuki Minami, a lawyer representing the woman, said the case is extremely unusual in that her request seeks to allow same-sex marriages through the change in the family register. In Japan, same-sex marriages are currently prohibited.

According to court papers and the transgender woman, she was born a male and married a woman when he was 29 and lives with their daughter, now an adult, in Kyoto.

In 2012, she was diagnosed with gender identity disorder and had sex reassignment surgery two years later to become a woman.

But since she was registered as male in the family register, she has experienced transgender inequality in that she was forced to use a changing room for men and was denied an inexpensive breast cancer screening checkup provided by the Kyoto city government.

Under the law that took effect in 2004, changing the sex in the family register is allowed only for people 20 or older who underwent sex change surgery, such as removal of their ovaries and testicles, who are not married and whose children are adults.

She said having to get a divorce would breach her right to pursue happiness and equality under the law, which are both guaranteed by the Constitution.

She also said her family supports her effort to change her sex in the register.