You domt know that that is a lie, its is perfectly possible, and in fact almost routine for men with 5ARD to do this. I was a research assisted in an IVF clinic years ago and we had a patient do so using ICSI. I dont know why the world collectively forgot about 30 years of scientific and medical knowledge about DSDs one day in 2016, or pretended to, but this is a well understood condition that Caster Semenya has, with well understood treatments including aided fertility. He is a biological male, however he chooses to identify, and so should not be in females sports.
This is just fact, and nothing to do with predjudice or racism. Im sorry if people don't have the scientific understanding to understand that to be the case, but it doesn't alter the facts of the matter. And that his children might be adopted or they might be biologically his using assisted reproduction. No one can say for sure, apart from him and his wife, beacsue he hasn't made a public statement about it.