(Reuters) - Double Olympic 800 metres champion Caster Semenya has lost her appeal to the Swiss Federal Tribunal (SFT) to set aside a 2019 Court of Arbitration (CAS) ruling that female athletes with high natural testosterone levels must take medication to reduce it.
But the South African has indicated that she may continue her battle in the European and domestic courts ahead of the Olympics in Tokyo next year, vowing to "fight for human rights".
Semenya approached the tribunal in May last year after CAS, sport's highest court, had ruled that the regulations of the sport's governing body World Athletics were necessary for athletes with differences in sexual development (DSDs) in races ranging from 400 metres to a mile to ensure fair competition.
The tribunal found the requirement of subjecting certain female athletes to drug or surgical interventions as a precondition to compete does not amount to a violation of Swiss public policy, Semenya’s lawyers said in a statement on Tuesday.
Testosterone increases muscle mass, strength and haemoglobin, which affects endurance.
Some competitors have said women with higher levels of the hormone have an unfair advantage.
"I am very disappointed by this ruling, but refuse to let World Athletics drug me or stop me from being who I am," Semenya said in the statement.
"Excluding female athletes or endangering our health solely because of our natural abilities puts World Athletics on the wrong side of history.
"I will continue to fight for the human rights of female athletes, both on the track and off the track, until we can all run free the way we were born.
"I know what is right and will do all I can to protect basic human rights, for young girls everywhere."
Semenya has already indicated that she would focus on the shorter 200 metres sprint event, which falls outside of the regulations, at the Tokyo Olympic Games that were postponed to next year due to the COVID-19 pandemic.
But Semenya's lawyer, Greg Nott, suggested this was far from the end of the road.
"This setback will not be the end of Caster’s story," he said. "The international team (of lawyers) is considering the judgment and the options to challenge the findings in European and domestic courts."
World Athletics told Reuters they would release a statement on the ruling in due course.