SYDNEY BAUER and RACHEL SAVAGE THE International Olympic Committee's move to drop its advice on testosterone levels for transgender athletes in the absence of scientific consensus leaves sports bodies facing tough decisions on who can compete, some experts have warned. The IOC this week reversed its 2015 guidance that transgender women should be allowed to compete in women's sport provided their testosterone levels are below a certain limit for at least 12 months before their first competition. It said there was "no definitive answer" on whether testosterone conferred a competitive advantage for trans and some intersex women and that its impact on…