D&C? When is it needed?

I misscarried on Tuesday the 9th. This is my second misscarrige this year, and my third in 7 years. I've never went in for them, and I've never had a d&c. I'm wondering if maybe this is the reason I keep misscarring? My first m/c was when I was 17, had my daughter at 19. I'm 23 now and January 22nd was my first this year, heavy bleeding, lots of clots, and the baby, i was about 14-15 weeks. This last one I was only about 5-6 weeks. Heavy cramping and bleeding and a whole lot of clots. The cramping lasted about 5 days. Usually only lasts about 2 maybe 3 days and done by the 5-6 day. I'm still an emotional wreck, and I wanna do whatever I can to not have to go through this again. Any advice?