I breast fed all three and had very little PPB with any of them. I had a bit with Jess, but I think it was more stress then PPB....we were beyond broke and I had three kids to feed,DH was NO help with the baby and it was all on me, etc.....
My depression didn't even come back till after I was done breastfeeding the last time. I used to deal with it as a teen, but the bouts of depression pretty much stopped after I had Josh(not counting my 9 month stint with depo shot nightmare).....then after Jess was about 18 months they started to come back.