I miscarried at 10 weeks pregnant. Even though it's been difficult emotionally, I'm anxious to become pregnant again. My doctor recommended that I wait until I've gone through 2 normal cycles before conceiving again. I had bleeding for 3 days about 4 weeks after my miscarriage--I think that was my period. Why do I have to wait?
First of all, I'm sorry for your loss. And I can appreciate that you want to be pregnant again--soon. Maybe having better understanding of your health care provider's recommendations will help.
After a miscarriage, your body needs time to return to a normal cycle. For example, the March of Dimes explains, "some pregnancy hormones (human chorionic gonadotropin, hCG) remain in the blood for 1 to 2 months after a miscarriage." Giving your body time to recover will also ensure that your uterus is free from any of the remaining tissue from the miscarriage. As you've already noticed, your body will most likely starting cycling again 4 to 6 weeks after miscarriage.
While not medically significant, to determine pregnancy and figure out your due date, which is important for tracking development early in pregnancy, your health care provider will need the date of your last period. If you don't have a period before getting pregnant again, your doctor will not have this information.
In truth, we have yet to determine how long a couple should wait after miscarriage to assure a better outcome. The March of Dimes advises that medically, you should wait until after at least one period, but based on your emotional health, you may want to wait longer. My recommendation is that you go with your doctor on this one.