Hyperandrogenism in athletics: a review of Chand v. IAAF

Published 07 August 2015 By: Darryl Hutcheon


The issue of whether women who naturally produce exceptionally high levels of testosterone can compete in women’s athletics events raises difficult questions about why men and women are separated in athletics and other sports and about what needs to be done to uphold that separation.

This article analyses the recent decision of a Court of Arbitration for Sport (CAS) Panel in Chand v Athletics Federation of India and the IAAF,1 which has engaged with these questions in great detail. It also considers the implications of the Panel’s decision to suspend the IAAF regulations governing the eligibility of hyperandrogenic women to compete in women’s athletics events.  


Hyperandrogenism means the biological state of a person whose body naturally produces an exceptionally high level of androgens (such as testosterone). The IAAF’s controversial Regulations Governing Eligibility of Females with Hyperandrogenism to Compete in Women’s Competition2 (“the Regulations”) set out a process by which women with hyperandrogenism can be barred from participating in female athletic events. The Regulations are based on the idea (discussed in more detail below) that women with hyperandrogenism enjoy such a competitive advantage over their rivals that competition between them is distorted.

Last week, in Chand v IAAF, the CAS Panel, by way of an Interim Arbitral Award, decided to suspend the Regulations. The Panel’s detailed decision illustrates the difficult questions of law, ethics and science which can arise from the separation of men and women in sports like athletics.



The Regulations (enacted in April 2011) aim to set out a “framework for the determination of the eligibility of females with Hyperandrogenism to participate in International Competitions… in the female category” (regulation 1.1). The Preface to the Regulations notes that the difference in athletic performance between men and women, which is the basis for their separation in competitions, is “known to be predominantly due to higher levels of androgenic hormones in males”.

In essence, the Regulations provide for a process of investigation into female athletes who have or are reasonably suspected of having hyperandrogenism. The investigation involves a series of medical examinations and assessments of the individual (though the exact process to be followed will depend on the circumstances of individual cases), carried out in accordance with the rules and guidance contained in the Regulations and their annexes. If an athlete does not consent to being examined, she will not be eligible to compete in women’s competitions.

Ultimately, it falls to an Expert Medical Panel (“EMP”) to consider the results of the investigation. Pursuant to regulation 6.5, the EMP:

shall recommend that the athlete is eligible to compete in women’s competition if:

  1. She has androgen levels below the normal range; or
  2. She has androgen levels within the normal range but has an androgen resistance such that she derives no competitive advantage from having androgen levels in the normal male range.

The “normal range” (which in context means the normal male range) is defined as a total testosterone level equal to or above 10 nmol/L.

If the athlete does not meet the criteria in regulation 6.5, the recommendation will be that she is ineligible to take part in women’s competitions. The EMP can further recommend conditions under which the athlete may compete (regulation 6.8). The most obvious condition would be submitting to medical treatment to reduce testosterone levels.

The IAAF Medical Manager then makes a final decision on the athlete’s eligibility to compete taking account of the EMP’s recommendation. Pursuant to rule 22 of the IAAF Competition Rules 2014-2015, athletes deemed ineligible may not compete in international or domestic competitions.



The arbitration process was initiated by Dutee Chand, a (now) 19-year-old Indian female athlete. Ms Chand is a highly promising runner who won gold medals at the Asian Junior Track and Field Championships in May 2014. In the months following those Championships, she underwent a number of medical examinations at the behest of the Athletics Federation of India (“AFI”) and the Sports Authority of India (“SAI”) with the apparent purpose of determining whether she had hyperandrogenism. The tests were carried out by reference both to the Regulations and to the Indian Ministry of Youth Affairs and Sport’s own Standard Operative Procedure for female hyperandrogenism.

The AFI and the SAI concluded that Ms Chand did have hyperandrogenism.3 The SAI then issued a number of public statements on 15, 16 and 17 July 2014. The first statement suggested that a “gender test” had been carried out on a female athlete and that she was not eligible to compete, before the subsequent statements clarified that the tests related only to hyperandrogenism and not to gender.

After these statements were made, Dr Payoshni Mitra made contact with Ms Chand. She was appointed by the SAI as a mediator and consultant for Ms Chand in late July 2014. However, though Ms Chand and Dr Mitra met with the SAI and the AFI on 14 August 2014, the position of both organisations remained that she should not be allowed to compete in women’s athletics events. By a decision letter received on 31 August 2014 (“the Decision”), she was told by the AFI that she was provisionally suspended from participating in any athletics events.4

Ms Chand then filed a Statement of Appeal at CAS on 26 September 2014 naming the IAAF and the AFI as respondents. She challenged both the Decision and the validity of the Regulations.

The case was heard on 23 – 26 March 2015.5 The Panel was comprised of the Hon. Justice Annabelle Bennett (of the Federal Court of Australia), Professor Richard H. McLaren and Dr Hans Nater, with Edward Craven, a Barrister at Matrix Chambers, serving as ad hoc clerk to the Panel.6 Several experts produced reports and gave evidence along with number of other witnesses including non-hyperandrogenic female athletes for both sides.



The Panel found that both the IAAF and the AFI had submitted to the ad hoc jurisdiction of the CAS (Award at para [424] and [436]). Further, the Panel only considered the challenge to the Regulations and not to the Decision (since India would in any event have to adapt its national practices if the Regulations were declared invalid) ([105]). The AFI did not participate in the final hearing but remained a party to the proceedings.

Ms Chand’s challenge rested on four grounds:

  1. The Regulations impermissibly discriminated against female athletes on grounds of a natural physical characteristic (namely their androgen levels) and/or sex (“Ground 1”);
  2. The Regulations were based on the factually flawed assumptions that men and women could be distinguished by reference to testosterone levels and that elevated levels of natural testosterone produced enhanced athletic performance (“Ground 2”);
  3. The Regulations were not proportionate to their legitimate objectives (“Ground 3”); and
  4. The Regulations were an unauthorized form of doping sanction in violation of the World Anti-Doping Agency Code7 (“Ground 4”).

The law applicable to the dispute was the IAAF Constitution,8 the IAAF Competition Rules9 and (except where inconsistent with those instruments) the law of Monaco ([440]).10 However, the Award equally refers to the Olympic Charter11 and generally to principles of international human rights law, and the parties do not seem to have disagreed about the substantive legal rules to be applied.



The Panel found for Ms Chand on Grounds 1 and 3 but dismissed her claim on Grounds 2 and 4.

The Panel’s reasoning on Grounds 1 and 3

The IAAF did not dispute that the Regulations prima facie discriminated on grounds of a natural physical characteristic and of sex (since no rules require men to be tested for endogenous testosterone levels). The IAAF accepted that it bore the burden of justifying that discrimination. The decision on both Grounds 1 and 3 therefore turned on whether the IAAF could demonstrate that the Regulations were necessary, reasonable and proportionate.

Both parties agreed that ensuring fairness in sport was a legitimate aim (though Ms Chand disputed the IAAF’s further suggestion that it was possible to aim for a “level playing field” in women’s athletics). On proportionality, Ms Chand claimed that female athletes in her position suffer a range of serious detriments (including stigma, the need to consent to invasive medical investigations and the long-term health risks associated with treatments to reduce testosterone levels) while the IAAF argued it was protecting the interests of other female athletes.

The Panel acknowledged the diligence and sensitivity with which the IAAF had drafted and applied the Regulations ([505]). However, it then stated that the Regulations – in taking effect to bar some athletes from participating in any competitive athletics, whether in the male or female category, in their natural state – were “antithetical to the fundamental principle of Olympism that “Every individual must have the possibility of practicing sport, without discrimination of any kind”” and imposed a significant detriment” on the athletes concerned ([513]). There was accordingly a high burden on the IAAF to justify the Regulations.

The Panel found that the premise of the Regulations was that hyperandrogenic females were at a significant advantage over other female athletes - greater than the advantage arising from any other single genetic or biological factor and comparable to the performance advantage that males typically enjoy over females. The IAAF effectively had to prove this premise to succeed on proportionality ([519]).

In finding that the IAAF had failed to do so, the “critical” consideration for the Panel was that there was insufficient evidence about the degree of the athletic advantage which hyperandrogenic females enjoyed over other females ([522]).12 While the average performance advantage of men over women in athletics was in the order of 10 – 12% ([522]), the evidence did not show whether the advantage held by hyperandrogenic females was of the same order (although one of the IAAF’s experts had estimated an advantage of around 3% ([525])). In those circumstances, the Panel could not say that the advantage was any greater from the “legitimate” advantages arising from factors such as “nutrition, access to specialist training facilities and coaching, and other genetic and biological variations” ([532]).

The Panel recognised that its reasoning left open the question of what “percentage increase” would be required for the Regulations to be considered proportionate. Notably, however, it did repeatedly contrast the 12% figure with advantages of 1% and 3% ([534]).

Ground 2

The burden of proof on ground 2 rested with Ms Chand.

Two important facts were agreed between the parties:

  1. A person’s Lean Body Mass (“LBM”) does have an impact on athletic performance and was the key reason behind the difference in performance between men and women ([133] and [496]). However, the parties disputed the relationship between endogenous testosterone levels and LBM;
  2. Exogenous (i.e. artificially introduced) testosterone also has a positive impact on athletic performance. This left in dispute the question of whether the same applied to endogenous (i.e. naturally occurring) testosterone.

First, the Panel accepted that there was a significant difference in the testosterone levels of normal populations of males and females ([494]).

Second, having considered the very substantial amount of evidence before it, the Panel concluded that Ms Chand had not proved that testosterone was not a material causative factor in athletic performance ([498]). It considered that her evidence did not sufficiently address the relationship between testosterone and LBM (which she had accepted to have an influence on athletic performance) ([458]), even though the Panel accepted that “the scientific and medical basis for the difference in LBM has not been established”. The fact that the elite class of athletes included low-testosterone men and androgen insensitive women (who are biologically incapable of deriving any benefit from androgens) was not enough to “tip the scales” ([489]).

Finally, the Panel considered whether there were any differences between endogenous and exogenous testosterone. (Notably, the evidence upon which the IAAF relied to refute Ms Chand’s case about the relationship between testosterone and performance largely related to exogenous testosterone ([491]).) Once more, the Panel stated that the issue had “not received sufficient attention” ([479]) and that further research was needed ([492]). However, again citing the burden of proof, the Panel only had to conclude that Ms Chand had failed to prove that there was a difference in the way the body processed endogenous testosterone ([488]).

Ground 4

Finally (and much more briefly) the Panel rejected Ms Chand’s argument that the Regulations amounted to a doping prohibition in breach of the World Anti-Doping Agency Code. The Panel considered it conclusive that the Regulations could not be said to involve any punishment or censure and did not serve any retributive or deterrent purpose ([542]). Further, the Panel noted that the Regulations related to endogenous testosterone whereas the anti-doping sanctions sought to cover external substances (at [542] and [543]). It described endogenous doping as “a contradiction in terms” ([543]).


On the basis of its conclusion on Grounds 1 and 3, the Panel suspended the Regulations for two years. However (and following from its conclusions) the Panel ruled that at any time within two years of its Award (dated 24 July 2015) the IAAF could submit further evidence addressing, “in particular, the actual degree of athletic performance advantage sustained by hyperandrogenic female athletes… by reason of their high levels of testosterone”. If the IAAF takes up this opportunity, Ms Chand will have the chance to respond and there may be a further hearing. If they do not, the Regulations shall be declared void at the end of the two-year period.



Perhaps the most notable aspect of the Award is that the central reason for the Panel’s conclusions on Grounds 1, 2 and 3 was the lack of compelling scientific evidence on the issues at hand.

The immediate consequence was that the incidence of the burden of proof was determinative. Thus on Ground 2 (the Regulations were based on factually flawed assumptions), where it was for Ms Chand to show the lack of a scientific basis for the Regulations, the uncertainty in the evidence favoured the IAAF. Yet on Grounds 1 (discrimination against female athletes on grounds of a natural physical characteristic/sex) and 3 (the Regulations were not proportionate to their legitimate objectives) the lack of compelling evidence favoured Ms Chand because the IAAF had the burden of showing proportionality.

As a short aside, the Award could perhaps have been clearer about the precise standard of proof which a party must satisfy when seeking to justify discrimination. The Panel stated that “the requisite standard… should be to a level higher than that of the balance of probabilities” since the IAAF was seeking to justify “discrimination of a fundamental right, which includes the right to compete ([443]). It stated that in this context the IAAF had to “overcome positively the onus to establish that justification” ([447]). Yet in its Conclusions section on justification, the Panel refers to the balance of probabilities test ([534]). Different CAS panels in cases relating to discrimination and to doping (described at [446]) have previously applied different standards of proof.

Further, given that the lack of compelling scientific evidence is what ultimately determined the outcome, the Panel’s conclusions are not definitive. As stated above, the Panel has afforded the IAAF an opportunity to adduce further evidence: it is possible that the Panel could reverse its own decision on proportionality in light of such evidence.

Nevertheless Ms Chand has reason to be hopeful. The Panel carefully scrutinized the available evidence, applied a high threshold to the issue of justification and did not accord extensive deference to the IAAF. The prospect of new evidence showing that hyperandrogenic women enjoy advantages equivalent to those enjoyed by men is perhaps quite low (in lieu of evidence that hyperandrogenic women are matching the performance levels of men). Finally, evidential uncertainty is a two-way street. If more research emerges to show that testosterone does not significantly influence LBM, or that exogenous and endogenous testosterone react differently in the body, that could make the case for invalidating the Regulations all the more compelling.

The insufficiency of the scientific evidence also perhaps meant that the Panel did not engage with other aspects of the parties’ arguments as much as it might otherwise have done. It is hard to tell what the Panel thought of the competing arguments about the “detriments” and “benefits” resulting from the Regulations. That is significant because in the author’s view, the degree to which hyperandrogenism impacts performance should not by itself determine the issue of proportionality. A person’s socioeconomic background, height, or access to high-altitude training facilities may well be a significant determinant of performance – but it is hard to imagine the IAAF arguing for bans (successfully or at all) based on those sorts of characteristics. There would need to be a convincing explanation of why hyperandrogenism (if it does significantly affect performance) is an illegitimate source of competitive advantage while those other characteristics are not.

A number of more specific questions arising expressly or implicitly from the proceedings remain to be determined. For example, how important is it that some of the other factors which can influence athletic performance (of which examples are given at [532]) are, at least in principle, not immutable, whereas the testosterone levels of a female athlete who does not have hyperandrogenism are effectively immutable? On the other hand, does the fact that there is no hyperandrogenism regime for men make it harder to justify the Regulations? In male athletics, especially high testosterone levels are considered to be a legitimate source of competitive advantage.



The immediate effect of the Award is that the Regulations (and national federation rules applying them) cease to apply. Women with hyperandrogenism are therefore cleared, at least temporarily, to compete alongside other women in domestic and international athletic events. What happens next depends on whether the IAAF adduces new evidence: the statement it released after receiving the Award indicates only that it will meet promptly with experts to discuss the ruling.13

Subject to that caveat, the implications for other sporting contexts are obvious. Sportswomen in other fields may feel encouraged to raise complaints and bring proceedings against the relevant bodies in their field (if they apply similar hyperandrogenism rules), especially given the Award’s emphasis on general principles of human rights law and the Olympic Charter (rather than just the specific rules of the IAAF).

Notably, the IOC adopted Regulations on Female Hyperandrogenism for the London Summer Olympic Games14 and the Sochi Winter Olympic Games.15 Though those Regulations are not in every respect identical to the IAAF Regulations,16 the IOC should think very carefully before adopting similar regulations for future Olympic Games.

There is also potential relevance for rules relating to the participation of athletes who have undergone gender reassignment. The IAAF’s Regulations Governing Eligibility of Athletes Who Have Undergone Sex Reassignment to Compete in Women’s Competitions17 are similar to the Regulations. They also require athletes to undergo tests following gender reassignment to measure their androgenic hormone levels. The Expert Medical Panel will then only recommend an athlete for eligibility if she has had sufficient medical treatment “to minimize any advantage in women’s competition” (regulation 8.4). The validity of those Regulations therefore also seems to depend on the assumed connection between androgenic hormones and sporting performance.

In sum, much is still at stake as scientists continue to probe the complex scientific questions that the Panel in Chand was forced to confront.18


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Darryl Hutcheon

Darryl Hutcheon

Darryl is a trainee barrister at Matrix Chambers in London. He is now practising in employment and public law. As a devoted follower of sport, Darryl is naturally interested in how the law applies to sports issues. His Chambers profile can be viewed here.

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