


Opponents have criticized such regulations as discriminatory against transgender and intersex women, disproportionately affecting women of color, and as causing violations of medical ethics. Proponents of such regulations regard them as necessary to ensure fair competition and women's safety. Since the mid-twentieth century, sports institutions have responded to the participation of transgender women, and women suspected to be transgender, male, or intersex, by adding eligibility requirements to women's sports variously determined by physical examination, sex chromosomes, and sex hormones. The controversy has caused debates regarding sex verification in sports. The American Medical Association states that legislation barring trans women from women's sports harms the mental health of transgender people. Supporters also argue that sport, particularly youth sports, is also about belonging, well-being, and socialization of young people. Supporters of transgender athletes argue that medically prescribed puberty blockers and estrogen suppress testosterone levels and reduce the muscle mass of transgender women, reducing possible competitive advantages. Opponents argue that transgender women have an unfair advantage over, and may endanger, cisgender women in competitive sports due to sex differences in human physiology, and that these differences are not sufficiently reversed by transgender hormone therapies.

The participation of transgender people in competitive sports, a traditionally sex-segregated institution, is a controversial issue, particularly the inclusion of transgender women and girls in women's sports. Law preventing trans athletes from participating in sport in their gender identity enacted, but currently blocked from enforcement via court order
