World Athletics President Sebastian Coe said the state of women's sports is "very fragile" and sports federations need to get it right when writing rules for transgender female athletes.
Coe's comments come after University of Pennsylvania swimmer Lia Thomas became the first transgender NCAA champion in Division I history by winning the women's 500-yard freestyle in Atlanta last week.
"The integrity of women's sport — if we don't get this right — and, actually, the future of women's sport, is very fragile," Coe was quoted as saying in British paper The Times on Monday.