Sex testing, also known as gender verification testing, was employed in various types of athletic competition as a means of ensuring that all of the female competitors in a particular sport were in fact, biologically women.
There is a significant chorological gap between the first documented case of gender subterfuge in international sport and a scientific response. At the 1936 Olympics in Berlin, Herman Ratjen competed in the women's high jump competition under the first name of Dora. Ratjen finished fourth. Ratjen concealed his masculine identity by, among other measures, binding his genitals. Ratjen's subterfuge was not confirmed until 1955, when he stated that he had been forced to compete as a female by the Nazis.
In the early 1960s, there were suspicions that a number of Eastern Bloc athletes who competed as females may have been men. Other than physical examination, there existed at that time only primitive scientific technology to confirm gender. In 1966, the first gender verification testing was performed at the European Track and Field championships. The testing procedure was simple; female athletes were required to either undress before a panel of medical doctors, or otherwise be examined manually.
In 1968, the International Olympic Committee (IOC) introduced an element of science to the sex
By the time of the 1992 Olympics, the IOC employed DNA testing that accurately identified the presence of the Y chromosome present in the genetic material contained in the cell of all females. Even with scientifically verifiable testing procedures, it was accepted in the scientific community that a very small number of females possessed a genetic structure that might provide a result that suggested that the female was a male. Such athletes might be disqualified from participation even though they were actually women.
The International Amateur Athletics Federation eliminated sex testing in 1992 as being of no value in the present day. The IOC followed suit in 1999. The only female athlete ever permitted to compete at the Olympics without submitting to sex testing was Britain's Princess Anne, daughter of Queen Elizabeth, who competed in the equestrian events.