Im sorry to hear of the loss of your 2nd bubba - its not easy is it?!
as for how long u should wait - i personally think that is entirley up to you and what u are comfortable with - I also suffered 2 MC last year - my DH and i tried straight away after AF came back.
Can i maybe suggest if u fall pregnant again you get your progesterone levels monitored thats if your dont know what is causing your MC- after my 2nd mc i went to see a doc who monitored by progesterone levels throughout my cycles and found out i had low progesterone which was causing my MC! So because of that i have now made it too 14wks preg tomorrow!!!
Once again im very sorry to hear of your loss - we are all here for you! take care