from that article
> The current IOC policy dictates that transgender women must have a testosterone level less than 10 nanomoles per liter, roughly the low end of typical male values. But because more than 99% of women have testosterone levels less than 3 nanomoles per liter, some researchers have suggested that limit is too high. Harper is among them. "If you're competing in the women's division, you should do so with women's hormone levels," she says. "I understand just how much difference they make."