At least 890 females have lost medals and awards to men self-identifying as supposed transgender women, according to a recently released report from the United Nations.

The new analysis, which centers on violence against women and girls, noted that the “replacement of the female sports category with a mixed-sex category has resulted in an increasing number of female athletes losing opportunities,” which includes over 600 female athletes losing medals across twenty-nine different sports leagues and competitions.

“Policies implemented by international federations and national governing bodies, along with national legislation in some countries, allow males who identify as women to compete,” the report said. “In other cases, this practice is not explicitly prohibited and is thus tolerated.”

The report cautioned that male athletes have distinct attributes, such as elevated strength and testosterone levels, that result in the loss of fair competition, as well as questioned whether the testosterone suppression requirements imposed by some sports leagues are sufficient.

“The testosterone levels deemed acceptable by any sporting body are, at best, not evidence-based, arbitrary and asymmetrically favor males,” the report added. “Females are usually tested randomly to ensure that they are not using performance-enhancing drugs, while males are often not monitored to ensure that they are taking testosterone suppression drugs. To avoid the loss of a fair opportunity, males must not compete in the female categories of sport.”

Surveys indicate that a large percentage of Americans believe that self-described transgender athletes should not be permitted to compete in sports leagues opposite their actual sex.