Gender Verification in Sports

Gender verification in sports (also known as sex verification, or loosely as gender determination or a sex test) is the issue of verifying the eligibility of an athlete to compete in a sporting event that is limited to a single sex. The issue arose a number of times in the Olympic games where it was alleged that male athletes attempted to compete as women in order to win, or that an intersexed person competed as a woman. The first mandatory sex test issued by the IAAF for woman athletes was in July 1950 in the month before the European Championships in Belgium. All athletes were tested in their own countries. Sex testing at the games began at the 1966 European Athletics Championships in response to suspicion that several of the best women athletes from the Soviet Union and Eastern Europe were actually men. At the Olympics, testing was introduced at the 1968 Olympic Winter Games in Grenoble. While it arose primarily from the Olympic Games, gender verification affects any sporting event. However, it most often becomes an issue in elite international competition.

While it would seem a simple case of checking for XX vs. XY chromosomes to determine whether an athlete is a woman or a man, it is not that simple. Fetuses start out as undifferentiated, and the Y chromosome turns on a variety of hormones that differentiate the baby as a male. Sometimes this does not occur, and people with two X chromosomes can develop hormonally as a male, and people with an X and a Y can develop hormonally as a female.