A storm erupted over the participation of Algeria's Imane Khelif and Taiwan's Lin Yu-ting at the Olympics after Khelif's Italian opponent pulled out of their bout less than a minute into the fight after taking a barrage of punches.
The boxing competition at Paris 2024 is taking place under International Olympic Committee rules after the IOC stripped the IBA of its status as the sport's global governing body over governance and finance concerns.
IBA chief executive Chris Roberts said he could not disclose the results of the gender eligibility tests but that the pair's disqualification from the 2023 women's World Championships meant the public could "read between the lines".
"The results of the chromosome tests demonstrated both boxers were ineligible," Roberts told a chaotic press conference that was late starting, suffered sound problems and was dominated by the IBA's Russian president's lengthy rants.
He said the results of the tests had been sent to the IOC in June last year and that it had done "nothing with it".
The dispute has revived debate over the balance between fairness and safety, particularly in women's sports, where differences of sexual development can result in a competitive advantage that might prove dangerous.
The IOC says the IBA is a discredited organisation, mired in financial opaqueness and compromised by ties to the Russian leadership.
"The content and the organisation of the IBA press conference tells you everything that you need to know about this organisation and its credibility," an IOC spokesperson said.
It has said that Khelif and Lin were "victims of a sudden and arbitrary decision by the IBA" to test them and that they were disqualified in 2023 without due process.
"We have two boxers who were born as women, raised as women, who have passports as women and who have competed for many years as women and this is a clear definition of a woman," IOC President Thomas Bach said on Saturday.
SPORT AND GEOPOLITICS COLLIDE
The IBA maintains it acted to protect women boxers.
Relations between the IOC and IBA soured following Russia's invasion of Ukraine in 2022, with the IBA run by Russian Umar Kremlev and with Russian state energy firm Gazprom being its main sponsor, though Kremlev said last year that the sponsorship had ended.
Bach has said the IBA's complaints are part of a broader campaign aimed at undermining the Paris Olympics, which Russia has been excluded from due to the war in Ukraine.
In a long and rambling presentation, Kremlev meandered from personal attacks against Bach to railing against the Paris Olympics' opening ceremony and defending his own fight against corruption.
"Today we are witnessing the death of female boxing, the corruption of judges. All of these happens when Mr Bach (is) president," Kremlev told the IBA press conference by video link.
Kremlev also said tests had shown both boxers had high levels of testosterone, without providing further details. The IBA's doctor Ioannis Filippatos said testosterone had not been tested for.
Alun Williams, professor of sports and exercise genomics at Manchester Metropolitan University, said that when considering if a person had an unfair advantage it was necessary to look at chromosomes, levels of testosterone and other hormones, as well as the body's response to testosterone.
"That then is a clinical assessment, which is really very invasive," Williams said. "Simply looking at someone's sex chromosomes ... is incomplete."
The gender furore has swept social media and seen people such as J. K. Rowling and Tesla founder Elon Musk voice their opposition to the two boxers competing at the Games.
Khelif's father said his daughter had brought honour to the family and described the attacks against her as "immoral".
Algerian boxer Roumaissa Boualem, who attended the press conference, said the IBA was talking "nonsense".
"We live in Algeria, she is born as a woman," Boualem told Reuters. "They (IBA) say they are protecting women, they are protecting athletes, but she also needs to be protected."
Taiwan President Lai Ching-te has hailed Lin's progress.
"In recent days, Taiwan's people have been indignant at the slander against her. Facing the challenge, Yu-ting is fearless and uses her strength to crush the rumours. Let us continue to cheer for her!" he said on Facebook on Sunday.
