By Alice Dreger
Published: October 24, 2009

Track and field’s world governing body has begun trying to devise new rules about who can compete as a woman. This comes nearly two months after being presented with the case of Caster Semenya, the South African runner whose sex was questioned when she won the 800-meter world championship.

Let’s start with the reasonable assumption that we want to maintain gender segregation in most sports. It provides girls and women — half the planet’s population — a real hope of winning. Without that hope, many may not bother.

The pickle, then, is how to maintain that segregation in the face of apparent challenges. A Renée Richards or a Caster Semenya doesn’t come along too often, but often enough that there needs to be explicit rules about who is considered a woman. But what rules?

The current policies of the International Association of Athletics Federations are vague, incomplete and contradictory. For example, one states that some women with some male-typical aspects (including, in some cases, a Y chromosome and testes) can play as women, but it doesn’t specify which combinations disqualify an athlete. This means a woman like Semenya can’t really know for sure, in advance of competition, if she should show up.

The I.A.A.F. requires that transsexual women have their hormone levels kept female-typical through removal of the testes and ingestion of female-typical hormones.

Fair enough. But it allows born-females with adrenal tumors to compete as women, even though their bodies may have higher levels of testosterone than the average male. Not too consistent.

Simply stating which conditions disqualify an athlete would be a step in the right direction, especially if the list is based on standardized principles. But even that may not seem fair for some conditions, because two women with the same diagnosis may have different anatomies and physiologies.

So what is the I.A.A.F. to do? I put that question to three physician-scientists of the sort the I.A.A.F. should be consulting.

Eric Vilain, a professor of human genetics and pediatrics at U.C.L.A., specializes in sex development, so he knows that looking at genes will not tell you simply how a body is functioning. And what we care about is function. “The best biological marker, if you want a level playing field, would probably be functional testosterone,” Vilain said. “There is a good correlation between functional testosterone and muscle mass.”

Measuring functional testosterone would mean not only measuring how much a body is making, but also the level of effect. Some people’s cells react more to testosterone than others’. The challenge of this, Vilain was quick to point out, is not only that high-quality testing is invasive, but that sports officials would have to decide where to make the cutoff.

This could have interesting — and unintended — implications for other athletes. Vilain says he wonders if men with functional testosterone levels below the cutoff would be allowed to compete as women, even though they are men. Would women under the cutoff not be allowed to bring themselves up to the line, to level the hormonal playing field? (The World Anti-Doping Agency allows men with “low” testosterone to take more if they establish a medical need.)

Philip Gruppuso is a pediatric endocrinologist and associate dean for medical education at Brown. Like Vilain, he says the I.A.A.F. must acknowledge that all it can do is make a reasoned choice among many imperfect options. He offered the possibility of using the ratio of androgens (including testosterone) to estrogens.

Vilain and Gruppuso noted that hormone levels at the time of competition were not all that mattered. An athlete’s biological history matters, too. A transsexual woman may now have female-typical hormones, but her bones and muscles developed under male-typical levels. Vilain’s research has suggested that the biological differences between men and women may depend on more than hormonal differences.

Gruppuso said that the I.A.A.F.’s response to the Semenya case revealed that the sport’s officials understood how complicated this matter was.

“It was so obvious — when they brought together gynecologists, geneticists, endocrinologists, psychologists — that there was no way to meld all the various areas of mammalian biology to come up with a single cohesive answer,” he said. “You can’t come up with a single binary answer to that question.”

Perhaps it would be best, Vilain and Gruppuso suggested, to devise an algorithm, one informed by all the sciences available. Nigel Paneth, a professor of epidemiology at Michigan State, says he imagines the I.A.A.F.’s developing clearer rules involving combinations of genetics, endocrinology, anatomy and psychology. This, he said, “would be more scientifically defensible than using just one criterion.” However, he warned, tests will sometimes be wrong, “and some people would no doubt be misclassified.”

This, then, is just some of what the I.A.A.F. must struggle with as it reworks its sex policies. How can it be consistent, across conditions, with regard to what counts as an unfair advantage? What error rate is it willing to accept for tests? Will the policy for various disorders of sex development match, in philosophy, its policies on transsexualism so transgender women are not cheated or benefited? How will the policies also affect athletes competing as men? Can the I.A.A.F. justify biological restrictions regarding some inborn conditions, given that natural variation has long been accepted as inevitable and fair in sport?

No easy job. And on top of all that, the I.A.A.F. will need to think about how its decisions will affect the tens of thousands of people who will, by implication, be judged male or female by these “verification” policies.

Gruppuso said he wondered what it would mean for his pediatric patients with disorders of sex development and gender-identity questions if sports officials and the public were to continue confusing who you are — boy or girl, man or a woman — with what your cells do.

Alice Dreger is a professor of clinical medical humanities and bioethics at the Feinberg School of Medicine, Northwestern University.

http://www.nytimes.com/2009/10/25/sports/25intersex.html