I did hot yoga in a lot of my TWWs, but you have to do what is right for you. Some months I did give it up in the wait, but it took me a long time to get pregnant so eventually i realized i was giving up an awful lot of yoga. I eventually did ivf and did not do hot yoga in that TWW, my doctor said no. Stay hydrated and be mindful of twisting and abdominal work and you should be OK. I know many people that continued hot yoga in pregnancy too, but I won't be one of them. Good luck! x