OSAKA (Kyodo) -- Go Shindo, a former women's boxing world champion who underwent gender reassignment surgery, announced Tuesday that he is retiring after his bid to continue boxing as a man was rejected by the Japan Boxing Commission.

The 37-year-old Shindo, a former WBC flyweight champion whose real name is Go Hashimoto, made the announcement at his gym in Osaka.

"I don't know if there will be more people like me in the future, but I may have opened that door. I have no regrets," he said.

The JBC has rejected Shindo's bids to box as a man since 2022. In December 2023, he took part in a semi-official three-round bout against a men's pro boxer but was knocked down and lost by unanimous decision.

Shindo continued to pursue a license to fight professionally as a man, but the JBC rejected his appeal in March, saying, "We cannot allow this at the present time due to the risk of problems arising from the standpoint of safety management."

Although Shindo considered fighting overseas, he decided this month to call it quits out of consideration for age and injury.

Regarding the JBC decision, Shindo said, "Sports have rules. I can't complain."