how do u know if you are having a boy or girl by there heart beat

It's a myth. Some moms can have higher heart beat rates with boys and girls. Just like all myths, some can be true for certain people

Higher heart rate means girl, lower means boy...

I'm having my second boy his was really high and many first sons was low

its not true but they say girls are higher boys are lower

I'm having a boy and his heart rate is always high so that's just an old wives tale lol

That myth is no where near right

thanks for the comments