Most wm then have the 19/20 wk to check the sex or just to check on bub.
Really? Pretty sure all the mum's i know have had it to check the health of their baby and to look for any signs of a problem.
ITA I certainly wasn't focused on the sex, I was more concerned that everything was in the right spot, that the placenta was doing what it needed to and my cervix length was doing ok...