Scans..

Elz
So my Aunty said that she read somewhere that ultrasound scans are bad for baby? 
I really want to get another scan... Had one at 9wks as I had bad cramping and my pregnancy symptoms disappeared... All was well. But I've had 3mc's before this one and I'm really anxious! 
My next scam through the Nhs is in 3wks time... But I was thinking of going next week privately? 
Thoughts?