New York (AFP) – A transgender American swimmer’s controversial career hung in the balance Wednesday after USA Swimming announced new rules, including testosterone limits, that could impact her ability to race competitively. Lia Thomas has dominated US collegiate women’s swimming as a student athlete at the University of Pennsylvania where, just a few years ago, she competed on the men’s team. Now, amid an uproar fueled by those who say Thomas has an unfair advantage, USA Swimming unveiled guidelines that do not mention the 22-year-old by name but will impact her future in the sport — althoug…