section_path: Categories/Men's and women's divisions
section_name: Men's and women's divisions
paragraph_text: Men's and women's divisions
  
  The foremost division of this kind is by sex: in athletics, men and women almost exclusively compete against people of the same sex. In contrast to the men's division, the development of the women's division has caused regular dispute in terms of eligibility. Several intersex athletes had success in the women's division in the early 20th century, such as Stanisława Walasiewicz and Mary Weston (later Mark), and the IAAF responded by introducing sex verification for all athletes in the women's category, beginning with the disqualification of sprinter Foekje Dillema in 1950 after she refused to be tested. Olympic champion Ewa Kłobukowska became the first athlete to publicly fail the test in 1967 and the humiliation she suffered as a result of the announcement led to sex tests becoming a confidential process. Hurdler Maria José Martínez-Patiño failed a test and was disqualified in 1985, but publicly fought the ban in court and was reinstated in 1988. In 1991, the IAAF replaced the sex chromatin test with general medical tests for athletes of all divisions, due to changes in ethical and scientific viewpoints.
  
  The question of eligibility for the women's division continued to be a contentious and public issue into the 21st century, with Caster Semenya and Dutee Chand bearing periods of ineligibility and taking the IAAF to the Court of Arbitration for Sport over their bans under the hyperandrogenism rules. An increasing number of trans men and trans women began to compete in the women's division in the 2010s, which caused other athletes in the division to raise questions of fairness in competition.
  
  The dispute reached new heights in 2019 with the United Nations Human Rights Council issuing a statement that the IAAF was breaching "international human rights norms and standards" through its practice of allowing some athletes to compete in the women's division only once they had lowered their testosterone levels through medical intervention. The IAAF and several prominent women athletes, such as Paula Radcliffe, said this was required in order to prevent a situation where countries deliberately sought out athletes who were intersex, transgender or had a difference in sex development in order to succeed in women's sport. Others have argued for the abolition of gender verification testing, with academic Maren Behrensen citing the harm to tested athletes' social and emotional well-being, the inaccuracy of the medical tests, the difficulty of determining the exact performance advantage provided by a given condition, and the moral risk of "gender-engineering" by setting a biological definition for a female athlete.