I have had 3 miscarriages and I understand. With all of mine it took about a month for my levels to drop low enough.I would have blood drawn about once a week. All of mine were different as was the time it took for my levels to drop and for my cycles to restart. Sometimes I would bleed for 3-4 weeks with the m/c and then the cylce wouldn't restart for several more weeks after that. I did not have a D&C with any of them. All 3 of my losses ranged from 6 weeks to 11 weeks. The Dr always told me to wait for 3 cycles before dh and I began ttc again.
I hope that this info helps and I am sorry for your loss.
Amanda