I know an OBGYN. She told me that you would be shocked at the number of times the determination of biological sex at the time of birth is not clear.
Further, this bill, while well intentions are present to protect biologically female athletes from being eclipsed by trans women, effectively has the consequence of banning trans people from collegiate athletics. That is no better a situation than having trans women competing with biological women.
Trans women should be allowed to compete with biological women, but biological women should be given proper recognition for their achievements. If a trans woman wins a race, the first biological female should also be recognized as the winner. In tournament sports, biological women would be given a second chance after losing to a trans woman. And so on. We can all learn how to get through this tough issue without having to exclude anyone or having biological female athletes losing opportunities in championships, etc.