In 2021, the IOC issued new guidelines calling on individual sports federations to develop their own participation policies rather than insisting on a blanket policy based on testosterone levels.

With the IOC currently in charge of Olympic boxing due to its dispute with the IBA and the Khelif-Lin controversy erupting, it is under growing pressure to issue its own stricter rules to protect the women’s category and ensure fairness and safety.

This is especially true after a number of sporting bodies have tightened their own gender regulations in recent years, excluding transgender women from elite women’s competitions and insisting that athletes with differences in sex development (DSD) must medically lower their testosterone levels. There is no indication that Khelif and Lin are transgender.

The IOC’s entry requirements for boxing have therefore not kept pace with those of other sports. The IOC abolished genetic sex testing in 1999 and appears to be opposed to changing the rules, partly out of fear of stigmatising people. It says that “everyone has the right to practice sport without discrimination”.

IOC President Thomas Bach said: “It is not as simple as some people would like to make it out to be today – that XX or XY is the clear distinction between men and women. That is no longer scientifically true.”

However, Bach also said: “If someone presents us with a scientifically based system for distinguishing between men and women, we will be the first to do so. We do not like this uncertainty. Therefore, we would be very happy to get to the bottom of the matter.”

An IOC spokesman also said that this was “not a black and white issue”.

They added: “There are many women with higher testosterone levels than men, so the idea that a test is some kind of miracle cure is not true. This is a minefield. If we can find consensus, we will certainly work to apply it. This is an issue across all sports and we are open to listening to anyone who has a solution to this issue. The IOC always tries to balance inclusivity and fairness, to put it more broadly, safety too. This is a difficult issue and something we need to look at.”

Critics of the IOC argue that such a balance is impossible and that fairness and safety must take priority.

The boxing controversy has fuelled calls for mandatory gender testing at future Olympics. Campaigners are calling for the reinstatement of a cheek swab test (which the IOC abandoned in 2000). They say the vast majority of female athletes are in favour of it. But others argue that more comprehensive testing is needed to be certain about a person’s genetic makeup, raising concerns about cost and invasiveness.