I'm often at the hospital with my child,who has a heart prlboem, and I have seen many children with congenital heart defects. Some of them need an open heart surgery or at least intensive care right after the are born, otherwise they won't survive. And only some biggest hospitals perform this kind of surgeries. Transport is also a big risk for these kids. Ultrasound is the only way to find out about the most serious defects before the birth and prepare for them. Therefore a woman can pick the best hospital to give birth in, where the baby gets all the help it needs right after the birth. Not getting an ultrasound is very risky in my opinion. I think the consequences can be much more serious than the possible dangers of an ultrasound.