I'm not saying that ultrasounds do not have their place, they really do! If we hadn't had one done on our 3rd child with hydrocephalus, we could have had far more serious consequences than what did occur.
What I was pointing out is that you usually only need one, not 4. The early ones are absolutely not necessary,
unless determining weather or not you have miscarried, especially since the first trimester is when the most damage can occur.
Providers used to be more cautious and only proscribing one at the 20 wk mark to determine if there are any abnormalities, and at the very end if there were complications. Now they are routinely given multiple times. People can walk in off the street and pay for a scan as many times as they want. The wealthy even buy there own ultrasound machines, so they can see their baby anytime they want.
The real issue is that there are studies that show the more times you get an ultrasound the more damage is being done. Unseen neurological damage is happening each time you get one. Getting one sonogram isn't going to do much damage, getting multiple ones could.
I know I will get one done at 20 weeks, because I believe in knowing about abnormalities before birth. I'm going to try and keep the # of scans down to a minimum and pass on the early scan to determine dates. I've always hated those trans-vaginal wands anyways