The N.C.A.A. on Friday cleared the way for the swimmer Lia Thomas, a transgender woman who has turned in the top times in the country in two events, to compete in the N.C.A.A.
championships next month, saying that implementing new rules for testosterone testing in the middle of the season would be unfair to transgender athletes.
The move is an about-face for the N.C.A.A., the organizing body in college sports, which said last month that it would require testosterone testing for the first time and planned to adopt standards set by sports federations beginning with the winter championships, which are held in February and March.
But that desire to immediately align with federation standards became untenable last week when U.S.A. Swimming announced stringent policies that in some ways seemed targeted toward Thomas, a senior swimmer at the University of Pennsylvania.