Austin Killips has become the first transgender athlete to win a UCI women’s stage race at the Tour of the Gila in New Mexico.
The 27-year-old American won stage five on Sunday to clinch the overall title, plus the ‘Queen of the Mountains’ jersey for best climber.
She thanked fellow riders for their support after “a week of nonsense on the internet”, but her win has reignited the debate over transgender athletes competing in female events. American three-time Olympian Inga Thompson said the UCI – cycling’s global governing body – was “killing off women’s cycling”.
Killips – who started racing in 2019 and also competes in cyclocross – finished eight seconds ahead of Mexican rider Marcela Prieto on stage five, and topped the general classification by one minute and 29 seconds.
She said on Instagram: “After a week of nonsense on the internet I’m especially thankful to everyone in the peloton and sport who continue to affirm that Twitter is not real life.
“I love my peers and competitors and am grateful for every opportunity I get to learn and grow as a person and athlete on course together.”
The UCI requires transgender women to suppress their testosterone levels to 2.5 nmol/L for a 24-month period prior to competing in female events.
It toughened it rules on eligibility in 2022, with previous regulations set at 5 nmol/L for 12 months.
The UCI’s transgender policy had been under review after being brought into the spotlight by British rider Emily Bridges, one of cycling’s most high-profile transgender competitors.
Its current policy differs from those of other international governing bodies, such as World Athletics and World Aquatics (previously called Fina), which have banned transgender women from competing in the female category at international events.
Last year, British Cycling said transgender women were no longer able to compete at elite female events it ran after the organisation suspended its current policy.
Thompson told the Telegraph she expected Killips to “potentially go on” to compete in the Tour de France Femmes and the Paris Olympics, adding that “…women are just quietly walking away. They think, ‘Why bother, if it’s not fair?'”.
Canada’s Olympic silver medallist Alison Sydor also criticised Killips’ participation, saying it was “no different functionally than doping”.
The Tour of the Gila is a UCI class 2.2 race – the lowest ranked UCI class – in New Mexico and has a total prize purse of $35,350 (£28,365), equal for both the men’s and women’s races.
In a statement, the Tour of the Gila said it “recognises the passionate debate regarding rider eligibility and classifications of riders set by UCI and USA Cycling and encourages UCI and USA Cycling to host an open discussion on the matter”.
Killips rides for the Amy D Foundation – an organisation set up in memory of American cyclist Amy Dombroski which “encourages and supports young women through cycling”.
BBC Sport has approached the UCI for comment.