I had a D&C on March 15th. One doc told me I didn't have to wait, another said 2 cycles. My MIL works as a L&D nurse, and she said they tell their patients to wait one normal cycle. I did so much research on this while I was in "limbo" as I call it after my surgery. I was trying to find somewhere some information where someone was just giving me permission!

I opted to wait one cycle for my own sanity really. Cause I kept telling myself, that if I do get pregnant again, and by some awful chance I had another m/c, I would probably blame it on not waiting or something, and it would just kill me.
AF returned for me after 5 weeks, and this was our week, so we BD'd like crazy, and I'm now in the 2ww. Waiting is the harest part. You wait...sometimes not knowing the fate of your pregnancy, you wait for the surgery, you wait for the bleeding to stop, you wait for AF...I know, it's all torture.
But really, I think it just all comes down to personal choice. A lot of people will tell you that docs say to wait so that you can better date the pregnancy, some try to say that if you don't wait, you stand a higher chance of another m/c, when actually that's just not proven. My doc said that getting pregnant right away stands no better chance of a m/c, you have the same odds as any other pregnancy.
Good luck to you with whatever you decide! Happy baby making!