when did period come after miscarriage?

Amanda
How did you predict when your next period will come after a miscarriage?  I miscarried at 6 weeks, had light spotting since week 5 and ultrasound confirmed at 6 weeks that I was miscarrying. Heavy bleeding from 9/9-9/12, light bleeding on 9/13 then nothing.  Hcg was back down to 2 as of 9/21. Doctor says it's safe to start trying when hcg has gone back down but I really would like to try and gage when my next ovulation/period will be.. anyone have experience with this?