Birth control

The question has come up on what kind of birth control I want after I have my daughter. I’m honestly undecided, I plan to breast feed, so I’m not sure the best kind. I know the depo can be used ( my dr told me) while breast feeding and since I refuse to get something inserted into me, I think that would be my only option. I can’t seem to decide on if that would be a good idea, since I was on it for 3 years before I had to switch to the pill. I also can’t help but feel guilty for thinking of putting them hormones and chemicals into my baby through my milk. They can have such negative affects on adults, so I’m worried about the kind of negative affects it could have on her tiny body. I obviously don’t want another baby anytime soon, but just undecided. The IUD or anything that has to be physically inserted is completely out of the question, I absolutely refuse to put any of them in my body! Anyone got any advice for me?