Missed miscarriage

Jenna • TTC#2. Have an almost 2 year old daughter. Miscarried at 10 weeks in April 2016. Chemical in July 2016.
Hi all - I found out Friday I've had a missed miscarriage at an ultrasound. I'm 9 weeks today but baby's heart stopped a little over a week ago. I'm debating between waiting it out for a natural miscarriage or having a D&C. How long after either of those did it take for your period to return?