I just recently had twin boys and I have an almost 3 year old girl. My husband and I do not want to get pregnant anytime soon. I'm looking in to getting an IUD. I know nothing about them really. Everything I read is either good or bad. Is the mirena better than the paragard? Or vise versa? I'm nursing the boys so I don't want anything that will mess with my milk or make me gain weight. Are these options a good choice for me?