I think, in general, it can take up to 6 months. But everyone is so different, plus it depends on what/how much you ate while preggo and if you exercised.  Sorry I can't give you any definite answers, but all 3 of mine were so different.  I still haven't lost the weight from baby #3 (prob 10 pounds to go until I'm back where I'd like to be), and he'll be 4 in May!