Caster Semenya's life changed because of eight seconds. It took 11 months before she could start to piece it back together.

In August 2009, the South African runner won the 800-meter world championship in 1:55:45. Immediately following the race, Semenya was forced to skip the postrace news conference and ushered out of the stadium.

A representative from the International Association of Athletics Federations, track and field's world governing body, took her place at the podium and explained that an eight-second improvement from her time at a race several weeks prior had triggered an investigation. The investigation included sex determination testing to confirm Semenya's eligibility to race as a woman.

A yearlong run of worldwide attention, embarrassment and questions about how sports should handle the delicate issue of sex determination followed. Semenya didn't compete for nearly the entire time. Though her test results remain private, she was cleared to run as a woman in July.

The string of events concerns Alice Dreger, professor of clinical medical humanities and bioethics at Northwestern University. The professor, who has no connection to Semenya or the testing in Semenya's case, has been outspoken that it is imperative for sports organizations to create policies on how to best handle athletes with potential disorders of sexual development.

Such issues are extremely complicated, Dreger says, and it is unfortunate that athletes may suddenly have their sex called into question on an international stage.

Alice Dreger, professor of clinical medical humanities and bioethics at Northwestern University. Alice Dreger

Formerly the chairwoman of the board of the Intersex Society of North America, Dreger became interested in the topic when a mentor suggested she research the history of sex anomalies. Dreger had assumed intersex conditions -- congenital conditions in which development of chromosomal, gonadal, or anatomic sex is atypical -- did not occur past the embryonic stage, but she eventually found hundreds of case studies that proved many adults lived long lives with such conditions. The findings surprised her, and she decided then to focus a portion of her career on the issue.

In addition to more than 100 speaking engagements at medical societies and universities, Dreger has also authored three articles in the New York Times on sex determination testing in sports. "Outside the Lines" recently had an extensive interview with Dreger on the topic. Some excerpts:

OTL: How are males and females typically defined in everyday life?

Dreger: When people talk about males and females in everyday life, they're usually thinking about things like genitals, and they're usually thinking about sort of how the body type is. They're using all sorts of identifying markers to decide, 'Is that person a man or a woman?' But in fact, sex is a lot more complicated than that, so sex isn't just what's on the outside of the body, and in terms of how sports works, what matters is actually what's on the inside of the body because that's the stuff that can give you certain advantages in terms of strength or endurance or grace or things like that that may be sex linked.

OTL: Why is it so difficult to categorize individuals as either male or female?

Dreger: In most cases, it isn't too hard to categorize people as males or females because there's no issue where we have to decide. But what's been happening in sports is that we've been pushed to the limit of science where we have people saying, 'No, you have to decide. Is this person a male or a female?' And once we start doing that, and we start looking at sex, we realize there are all these components within sex.

There's genes, there's genitals, there's gonads, there's hormones, there's all these different components and it isn't easy to say, 'Well, this is the one thing that makes you male or makes you female,' because there's overlap in all of those things. XX [chromosomes] doesn't make you female, it makes you likely to be female. XY doesn't make you male, it makes you likely to be male. But that alone does not tell us what you are.

OTL: What is considered an acceptable natural advantage?

Dreger: What people consider an acceptable natural advantage, I think, depends on the individual. It's one of those, 'I know it when I see it.' For some reason, when it comes to sex people get a lot more uptight about natural competitive advantage and I think it's because it does cause us to recognize that sex is not easily divided into two categories. If somebody has a natural advantage with regard to oxygen processing or their red blood cells or whatever it is, it doesn't push against a social norm.

If we're saying a woman has naturally high level of androgens, it begins to push against the social norm that says women are supposed to be separate from men in all ways, and then people get really upset and really uptight.

OTL: With gender and sports, what constitutes an unfair advantage?

Dreger: We don't say to the men who happen to make huge amounts of testosterone, 'Well, you make too much. You make way more than the average guy and therefore you've got too much.' We don't say that to the men, so the men are not being subject to the same level of scrutiny that women are. And that's one of my concerns actually is: Why are men not being subject to the same level of scrutiny as women?

One of the things that we know is that, for example, it seems to be the case that grace is sex-linked, and so the ability to be graceful seems to be easier for women than it is for men. If we have a situation where a man is particularly graceful in a sport that rewards grace -- say, for example, figure skating -- why is it that we don't say to the man, 'Well, you're too feminine to compete?' I don't understand why we don't find it offensive also to say to a women who's very strong, 'You're too masculine to compete.'

It seems to me both of them are kind of ridiculous, and what we should say is there's natural variation within each sex and sometimes that natural variation is going to give some people advantages and some people disadvantages and that's what sports is.

OTL: So where do you draw the line?

Dreger: I don't think you can simply say here's the line, other than to admit you're just drawing a line, other than to just say, just like we draw the line at where the goal line is when we go out to a field to play soccer, we're going to do the same thing with testosterone, just draw a line and say that the people on this side of it are allowed to compete as women and the people on this side of it are not allowed to compete as women.

OTL: What policy, if you were talking to the IAAF today and the IOC, what would you recommend?

Dreger: My inclination would be to say go with if you were born a girl, raised as a girl, you're allowed to compete as a female, and just leave it at that. Recognize that just like pituitary overdrive gives you an advantage in terms of height, in terms of hand size, in terms of foot size for certain sports, recognize that testicular overdrive or having testes rather than ovaries or having adrenal glands in high gear, may give you an advantage, and just recognize that glands differ by body, just as blood cells differ by body, bone type differs by body and recognize that we just have to live with that difference.

I would be inclined to go in that direction. I do recognize that that would upset a lot of women athletes who feel that it would be unfair, but I would ask them: Why aren't you caring about all the other things that would count as unfair? Is it because you would care about them if you could challenge it and you're just not able to challenge it? That's probably the answer. Otherwise it seems to me that you, you have to recognize that sometimes people are going to have an advantage over other people.

OTL: What if there are athletes out there who say, 'Sure, she's born and raised as a female, but clearly something's going on here where it's maybe not a willful advantage but it's an unfair advantage.'

Dreger: There are some people born with pituitary conditions that cause them to produce totally abnormal levels of growth hormone and they end up very tall with very big hands and very big feet and they end up in the NBA. We don't say to them, 'You're not allowed to compete in the NBA because you happened to have had a pituitary condition that gave you a hormonal advantage.' Why?

Why do we do that when it comes to sex but we don't do that when it comes to growth? It's the same thing. It's a gland producing a high level of a hormone that's not normally there that gives you a competitive advantage.

OTL: You mentioned it's tough to come up with a definitive policy. Why is it so difficult?

Dreger: I think it's hard to come up with a definitive policy because sex is complicated and the people longing for a policy are longing for a simplistic answer to sex. They're not just longing for a simplistic policy, they're longing for a simplistic reality of sex and that's not going to happen, so it's going to be difficult for the IAAF to come up with a policy that is as scientifically sophisticated as it needs to be and as simple as people want it to be.

Nature doesn't draw the line for us, we have to draw the line on nature. And so where sex is concerned nature's not going to tell us, 'This is male and this is female.' We have to say to nature, 'You've presented us a mess,' and we're going to say, 'This is where we're drawing the line and you're going to keep confusing us, but we're going to do it here.'

OTL: Why is the IAAF having such a tough time creating this policy?

Dreger: If there had been a simple answer to this, this would have been solved 50 years ago, and instead it's only getting more difficult to figure out how to answer this problem that nature presents to us. Nature is a slob. Humans like their categories neat. They like their categories of sex neat.

They like their categories of age neat, so for example, we say to people, 'At the age of 18 you may vote but at the age of 17 and 360 days you may not vote.' We say, 'You may drink at the age of 21 but not at the age of 20.' Why? Because humans like to create terribly neat categories out of nature because it allows us a nice, tight social organization. The truth is, nature doesn't care that we like nice, neat social organizations. Nature likes variety.

Lindsay Rovegno is a producer for ESPN.