Gender Prediction

people always say " if your belly is pointy , and low it's a boy " and if it's round " and high it's  a girl 
i've seen the pointy saying be true for all boys i've never seen a mom with a pointy belly say she's having a girl however the girl saying about the round belly I have encountered 2 women that looked like they were having girls and when I asked , they were actually having a baby boy .
so has this been true for any of you ladies ? and for you ladies with round bellies are you really having a girl or are you having a baby boy ?