Sex verification in sports also known as gender verification , or as gender determination or a sex test occurs because eligibility of athletes to compete is restricted whenever sporting events are limited to a single sex , which is generally the case, as well as when events are limited to mixed-sex teams of defined composition e. Practice has varied tremendously over time, across borders and by competitive level.
Issues have arisen multiple times in the Olympic games and other high-profile sporting competitions, for example allegations that certain male athletes attempted to compete as women or that certain female athletes had intersex conditions perceived to give unfair advantage.
The topic of sex verification is related to the more recent question of how to treat transgender people in sports. Sex verification is not typically conducted on athletes competing in the male category because there is generally no perceived competitive advantage for a female or intersex athlete to compete in male categories. Sex verification in sports began in the s with "femininity certificates" provided by a physician.
It subsequently evolved into visual inspections, physical examinations, chromosome testing, and later testosterone level testing. Sex verification can be substantially more complicated than checking whether a person's sex chromosome pair [ a ] is XX vs. XY, or comparing their levels of key sex hormones to distinct reference ranges, to determine an athlete's sex. This is due to variations in human biology where some people are not unambiguously female or male , not all cells in a person's body have the same genotype or the presence of other atypical genetic condition.
These reasons, among others, led sporting bodies to abandon chromosome testing towards the end of the 20th century and use hormone testing instead. The downside of hormone testing, however, is that policies on hyperandrogenism women with naturally higher testosterone were required, which have sparked both public debate and legal battles.
