Controversial transgender swimmer Lia Thomas will not take part in the upcoming Paris Olympics after losing a legal battle in which she argued the rules prohibiting her from participating were “invalid and unlawful.”

Thomas, 25, who transitioned to female via hormone therapy after competing for three years as a male on the University of Pennsylvania swim team, dominated the field of biological women to become the first openly trans person to win an NCAA Division I title in 2022.

Her ascent sparked an impassioned national debate about whether it was fair for biologically male athletes who change their gender to compete in female sports leagues.

Traпsgeпder swimmer Lia Thomas lost her appeal agaiпst a rυle from World Aqυatics goverпiпg body barriпg traпsgeпder womeп from competiпg iп womeп’s races. AP Photo/Josh Reyпolds, File

Thomas woп a womeп’s swimmiпg NCAA title at the Uпiversity of Peппsylvaпia iп 2022. USA TODAY Sports

In a subsequent attempt to include as many athletes as possible, World Aquatics introduced a new “open” category inclusive of transgender swimmers, which was meant to debut at an event in Berlin last October, The Guardian noted.

However, the category was canceled after nobody signed up to enter the field.