I had my baby already but im still itchy all over my body when will this go away?

I don't remember ever itching after having any of my children (I have four children), unless you count the time I got hives when my first child was about three months old. I don't think it had anything to do with postpartum, though; I think it was stress. You should probably talk to your ob-gyn about the itching to figure out what's causing it and to find treatment for it.