The arm implant is fine for breastfeeding and so it the IUD. Some pills are okay, but not usually recommended with a new baby and mom being so forgetful.
They don't usually want u to start birth control until 6 weeks after. And the pill, shot and implant all affect your milk supply. So you can get an IUD but that's pretty much all...but I've heard breastfeeding delays ur period for a while, so that could prevent u from getting preggo. Im planning on using the IUD and just getting it taken out in a couple years when I decide I might wanna have another child.