Why do so many drs do early us?

[Mirasmom]

Feel like every other thread is about how someone's early us didn't show a baby.....why do so many drs do so many ultrasounds? My dr is very hands off, I know, but still? We do one us at 20 weeks. Now granted I don't have complications and I know that situation is different, but I feel like nearly every dr now does at least 3 or 4 ultrasounds throughout. Why! They r so unnecessary! Even for dating. Really it's unnecessary. Edd is ESTIMATED. There a VERY few people that can't estimate when they ovulated with At least a week or two give or take. And really that's accurate enough bc u will be measuring and getting your 20 week scan for anatomy and also if you are going to truly let the baby come when It comes. I guess I just don't get it. Not only why do drs do them, but I can't believe insurance PAYS for them.