Breastfeeding is said to be the best way to lose weight after having a baby as it burns off so many calories. From my own experience I would say this is true as with both my children I got back to my pre pregnancy weight after just a few months of feeding them. However, not all women want to breastfeed so there are others ways to control weight. Obviously diet will be important too and gentle exercise, nothing too strenuous as the body takes time to recover after carrying another little life and giving birth. I used to love going for leisurely walks with my baby in the pram and the fresh air did us both good. Your doctor can also give you exercises that are suitable for women who have just had children or you could even look online but remember it can take time to return to what you were before so don't overdo it and enjoy your baby.