• 1. Dora Ratjen

    For the 1936 Olympic games in Berlin, Adolf Hitler wanted to show the world the supremacy of the Aryan race. German, Dora Ratjen, notable for her deep voice and her refusal to share the shower room with the other female athletes, was Germany’s entry for the women’s high jump. She came in fourth. Britain’s competitor, Dorothy Tyler, who won a silver medal, remembers her. “I had competed against Dora and I knew she was a man,” she says. “You could tell by the voice and the build.” Ratjen was discovered to be a man on his way back from the European Championships at a train station in Germany. Although Ratjen was wearing a skirt, two women spotted him with a five o’clock shadow. A doctor was summoned and Ratjen’s sex was revealed. In 1938 Ratjen was barred from further competition. via 1 via2.

  • 2. Stella Walsh

    At one point, Stella Walsh, a Polish-American sprinter, was the fastest woman in the world. She won gold in 1932 and silver in 1936 for the 100m sprint. During her career, she set more than 100 national and world records and was inducted into the American Track and Field Hall of Fame. She lived her entire life as a woman, and even had a short-lived marriage to an American man. In 1980, Walsh was killed by mistake during an armed robbery at a shopping mall in Cleveland, Ohio. The postmortem revealed she had male genitalia. She was also found to have both male and female chromosomes. via .

  • 3. Sin Kim Dan

    Dan broke the women’s records for 400m and 800m in 1961/62. She was the first woman to run 400m in less than 52 seconds. In 1963 in Moscow, other female sprinters refused to run against her because she looked like a man. At that same time a South Korean man claimed that she was his son who had disappeared during the war. Obligatory sex-testing for international athletics was introduced in 1966, and for whatever reason, Sin did not compete after that. via.

  • 4. Edinanci Silva

    Born with both male and female sex organs, the Brazilian judo player had surgery in the mid-90s so that she could live and compete as a woman. According to the IOC, this made her eligible to participate in the games and she competed in Atlanta 1996, Sydney 2000 and Athens in 2004. In Sydney, she beat the Australian Natalie Jenkins, who raised the issue of Silva’s gender in a press conference, constantly referring to her as “he” via.

  • 5. Tamara and Irina Press

    Sisters Tamara and Irina Press won five track and field Olympic gold medals for the Soviet Union, and set 26 world records in the 1960s. Their careers suddenly ended at the time that gender verification was introduced. Critics have suggested that the Presses were actually male, or perhaps hermaphrodites. via.

  • 6. Heidi Krieger

    It is believed that as many as 10,000 East German athletes were caught up in a state-sponsored attempt to build a race of superhuman communist sports heroes and force-fed cocktails of steroids and other performance-enhancing drugs. One of them was Heidi Krieger, a shot putter. When she was 16, her coach put her on steroids and contraceptive pills and she gained weight, built muscle and started to develop body hair. By 1986, aged 20, she was European champion and an Olympic shotput gold medalist. In the mid-90s, Krieger underwent gender reassignment surgery and changed her name to Andreas. via.

  • 7. Ewa Klobukowska

    Eda was a Polish sprinter who won the gold medal in the women’s 4×100 m relay and the bronze medal in the women’s 100 m sprint at the 1964 Summer Olympics in Tokyo. Klobukowska was the first Olympic athlete to fail a gender test. Having registered “one chromosome too many”, she failed an early form of the chromatin test in 1967 and was subsequently banned from competing in professional sports. via.

  • 8. Santhi Soundarajan

    Santhi Soundarajan, a middle distance runner from India, won a silver medal at the 2006 Asia Games. She was stripped of her medal after she failed a verification test. via.

  • 9. Mary Edith Louise Weston

    Mary Edith Louise Weston of Great Britain was the best shotputter from 1924 to 1930, and the best javelin thrower in 1927. She still holds Great Britain’s shot put record. Mary Edith Louise Weston became Mark Weston in the mid-1930s. via.

  • 10. Iolanda Balas

    After mandatory gender testing was implemented in the 60’s, high jumper Iolanda Balas refused to compete in the Olympic Games. She went to the Budapest games – but only as a spectator, wearing an Ace bandage. She was suspiciously, according to Rumanian track officials, suffering from a “calcified right tendon,” and was said to never be able to compete again. via.