How sex eligibility rules for female athletes work

By GRAHAM DUNBAR

PARIS (AP) — Women’s boxing at the Paris Olympics has highlighted the complexity of drafting and enforcing sex eligibility rules for women’s sports and how athletes like Imane Khelif of Algeria and Lin Yu-ting of Taiwan are left vulnerable in the fallout.

When eligibility for women’s events has come into question, it often has been a legally difficult process for sports bodies that has risked exposing athletes to humiliation and abuse. In the 1960s, the Olympics used degrading visual tests intended to verify the sex of athletes.

The modern era of eligibility rules are widely known to have started in 2009, after South African 800-meter runner Caster Semenya surged to stardom on the track as an 18-year-old gold medalist at the world championships.

Semenya, the Olympic champion in the 800 meters in 2012 and 2016, is not competing in Paris because she effectively is banned from doing so unless she medically reduces her testosterone. She is, however, still involved in a legal challenge to track’s rules, now into its seventh year.

Here’s a look at sex tests in sports and the complexity they create amid changing attitudes toward gender identity:

What is the criteria for female participation?

Testosterone levels — not XY chromosomes, which is the pattern typically seen in men — are the key criterion of eligibility in Olympic events where the sport’s governing body has framed and approved rules.

That’s because some women, assigned female at birth and identifying as women, have conditions called differences of sex development, or DSD, that involves an XY chromosome pattern or natural testosterone higher than the typical female range. Some sports officials say that gives them an unfair advantage over other women in sports, but the science is inconclusive.

Semenya, whose medical data proved impossible to keep private during her legal cases — has a DSD condition. She was legally identified as female at birth and has identified as female her whole life.

Testosterone is a natural hormone that increases the mass and strength of bone and muscle after puberty. The normal adult male range rises to multiple times higher than for females, up to about 30 nanomoles per liter of blood compared with less than 2 nmol/L for women.

In 2019, at a Court of Arbitration for Sport hearing, track’s governing body argued athletes with DSD conditions were “biologically male.” Semenya said that was “deeply hurtful.”

Semenya’s case played out very publicly before 2021, when gender identity was a big story at the Tokyo Olympics and in society and sports in general. She took oral contraceptives from 2010-15 to reduce her testosterone levels and said they caused a myriad of unwanted side effects: weight gain, fevers, a constant feeling of nausea and abdominal pain, all of which she experienced while running at the 2011 world championships and 2012 Olympics.

Female athletes of color have historically faced disproportionate scrutiny and discrimination when it comes to sex testing and false accusations that they are male or transgender.

Why does sex verification testing differ between sports?

Each governing body of an Olympic sport is responsible for drafting its own rules, from the field of play to who is eligible to play.

Women’s boxing came to the Paris Games with effectively the same eligibility criterion — an athlete is female in her passport — as at the Rio de Janeiro Olympics in 2016 after the International Boxing Association was permanently banned from the Games following decades of troubled governance and longstanding accusations of a thorough lack of normal transparency. Much has happened in the science and debate in those eight years.

Since the Tokyo Games in 2021, track’s World Athletics tightened the eligibility rules for female athletes with DSD conditions. Starting in March 2023, it required them to suppress their testosterone levels below 2.5 nmol/L for six months, commonly through hormone-suppressing treatment, to be eligible to compete.

That was half the level of 5 nmol/L proposed in 2015 for athletes competing at distances from 400 meters to 1 mile.

World Athletics followed another major sport — World Aquatics — in prohibiting transgender women from competing in women’s races if they had undergone male puberty. The International Cycling Union also took this step last year.

The swim body’s world-leading rules additionally require transgender women athletes who did not benefit from male puberty to maintain testosterone levels below 2.5 nmol/L.

World Aquatics is not actively testing junior athletes. The first step for athletes is that national swim federations “certify their chromosomal sex.”

Similarly, soccer’s world body FIFA defers to its national member federations to verify and register the sex of players.

“No mandatory or routine gender testing verification examinations will take place at FIFA competitions,” it said in a 2011 advisory that is still in force and has been under a lengthy review.

Why do governing bodies care about who identifies as female?

Many sports bodies try to balance inclusion for all athletes and fairness to all on the field of play. They also argue that in contact and combat sports, like boxing, physical safety is a key consideration.

In the Semenya case, the judges at the Court of Arbitration for Sport acknowledged in a 2-1 ruling against her that discrimination against some women was “a necessary, reasonable and proportionate means” to preserve fairness.

Male athletes are not required to regulate their natural levels of testosterone, and female athletes who do not have DSD conditions also can benefit.

“There are many women with higher levels of testosterone than men,” International Olympic Committee spokesman Mark Adams said in Paris as the women’s boxing debate has raged. “The idea that a testosterone test is some kind of magic bullet is actually not true.”

What does the IOC require?

The IOC is at times very powerful and at others not at all.

The Switzerland-based organization manages the “Olympic Charter” book of rules, owns the Olympics brand, picks the hosts and helps fund them through the billions of dollars it earns selling the broadcasting and sponsor rights.