My kids gave birth to a son on Thursday. B”H we knew it was going to be a boy, and had certain things bought (paper goods, decorations, etc.) or baked and frozen. It was VERY hectic erev Shabbos, and would have been a madhouse if we were not prepared in advance. we left SOME things undone, because until a baby is born, we don’t believe in being completely prepared, but it was much easier this time, knowing we had most things in place.
As a parent, had I been able to find out each time, I would have not wasted a second in finding out! In the olden days, our ancestors did not have the ability to find out as we do now. That does not mean it’s wrong to find out when we clearly can.