When are we most fertile after miscarriage?

Aine • Baby Noah arrived 10th March 2017 🌈
I had a missed miscarriage and on Saturday I miscarried naturally. We both want to try for our rainbow baby, and have heard some people conceive before their Af returns after miscarriage. But I don't know when I am likely to be most fertile... Has anyone got any advice or has anyone become pregnant again before Af returned?