Scans

I've been seeing alot of 4 wewk scand, 12 week scans, 16 week scans, and then many more scans. I've had 1 scan at 8 weeks ans my next isn't due until week 16. Have you ladies simply requested more scans, or were they dr suggested? I don't want to sound crazy but i wouldn't mind seeing my little one again on that screen. What is tour scan history?