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Multiple Olympic and World Champion runner Caster Semenya has lost her case against the International Association of Athletic Federations (IAAF) rules requiring her to take testosterone lowering agents to compete in sports. In this press release, Professor Julian Savulescu from the Wellcome Centre for Ethics and Humanities and the Uehiro Centre for Practical Ethics discusses this ruling and argues in defence of intersex athletes.

The Court of Arbitration for Sport (CAS) has announced that multiple Olympic and World Champion runner Caster Semenya and other athletes with disorders of sex (DSD) conditions will have to take testosterone lowering agents in order to be able to compete in her events.

Reducing the testosterone levels of existing intersex female athletes is unfair and unjust.

The term intersex covers a range of conditions. While intersex athletes have raised levels of testosterone, its effect on individual performance is not clear. Some disorders which cause intersex change the way the body responds to testosterone. For example, in Androgen Insensitivity syndrome, the testosterone receptor may be functionless or it may be partly functional. In the complete version of the disorder, although there are high levels of testosterone present, it has no effect.

As we don’t know what effect testosterone has for these athletes , setting a maximum level is sketchy because we are largely guessing from physical appearance to what extent it is affecting the body. It is not very scientific. We simply don’t know how much advantage some intersex athletes are getting even from apparently high levels of testosterone.

It is highly likely that many winners of Olympic medals and holders of world records in the women’s division will have had intersex conditions historically. It is only recently we have become aware of the range of intersex conditions as science has progressed.

These intersex women have been raised as women, treated as women, trained as women. It is unfair to change the rules half way through their career and require them to take testosterone lowering interventions.

It is a contradiction that doping is banned because it is unnatural, risky to health, and reduces solidarity. But in these cases sporting rules will force a group of women to take unnatural medications, with no medical benefit, in order to alter their natural endowments. So much for solidarity. Elite sport is all about genetic outliers. Cross country skier Eero Mantyranta won seven Olympic medals in the 1960s, including three golds. He had a rare genetic mutation that means the body creates more blood cells. The oxygen carrying capacity can be up to 50% more than average. This is a huge genetic advantage for endurance events like cross-country skiing. WADA say “the spirit of sport is the celebration of the human spirit, body and mind”, but in this case, the rules seek to limit and quash bodies that don’t fall into line with our expectations.

It is true that the rules of sport are arbitrary. What defines man and woman will always have borderline cases. But it is imperative these individuals are not unfairly disadvantaged. It is unfair to take away a person’s life and career because you choose to redefine the rules.

CAS agreed that the rules are unfair, but found the unfairness justified,

The panel found that the DSD Regulations are discriminatory but the majority of the panel found that, on the basis of the evidence submitted by the parties, such discrimination is a necessary, reasonable and proportionate means of achieving the IAAF’s aim of preserving the integrity of female athletics in the restricted events.

Yet there is another option: to implement the rules prospectively by allowing a “grandmother” clause for existing athletes who identify and were raised as women. Then testing for new athletes could take place early as soon as puberty is complete to identify athletes who would come under the DSD definition. Affected athletes could make an informed choice about continuing to compete at the cost of being required to take testosterone lowering agents. This would still deny them the opportunity of competing to their full potential, but it would at least prevent individuals from investing their lives in a sport they would either not want to or be able to compete in.

Intersex conditions can restrict people’s life options. In many cases, it is not possible to have a biologically related child or carry a pregnancy. Unfortunately, it can still carry stigma and discrimination (indeed CAS agree this is an example of it). One possible upside is an advantage in sports. This should not be denied.

Sport is based on natural inequality. If this is of concern to the authorities, I have argued that physiological levels of doping should be allowed. This would allow all women to use testosterone up to 5nmol/L, as can occur naturally in polycystic ovary syndrome and which the IAAF has considered an upper limit for women with intersex conditions. This would also reduce or eliminate the advantage some intersex athletes hold.

The rules of sports are arbitrary but they should not be unfair. Changing the rules to exclude a group of people who signed up under the current rules is unfair. A change for future generations of athletes would be less unfair, but I believe that it will make for a less interesting competition and will still disadvantage some women.

There is no fairy tale ending to this story. Someone will be a loser. But that is always the case in sport.

Professor Julian Savulescu
Uehiro Chair in Practical Ethics
Director, Oxford Uehiro Centre for Practical Ethics
Co-Director, Wellcome Centre for Ethics and Humanities
University of Oxford
Visiting Professorial Fellow
Murdoch Children’s Research Institute


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Further resources

Foddy B, Savulescu J. Time to Re-evaluate Gender Segregation in Athletics, BJSM

*This article has been accepted for publication in British Journal of Sports Medicine, 2011 following peer review, and the Version of Record can be accessed online at

Quote from BJSM article: “A ‘hormonal level-playing field’ would require not only an assay of athletes’ androgen concentrations, but also an assessment of the competence of their androgen receptors. That is, it would require some kind of test of the functionality of the androgens in vivo. This would be very difficult at present to do. But without such a test, it is impossible to tell how much advantage an athlete is gaining from his or her biology. If we segregate athletes using a simple testosterone test, we simply guarantee that the winners in the ‘women’s’ league will be those with the most sensitive androgen receptors—probably genetic males with low serum testosterone.”




This press release first appeared on the Practical Ethics - Ethics in the News blog. Read the original article.