"when breastfeeding is combined with ABM, the ABM negates the protective properties of breast milk". I read recently that when you "combine" human milk and ABM in the same bottle the ABM does take away part of the immunological element of the human milk. It was suggested to give the ABM without mixing it with human milk. A working mother would probably do just that. ( I'm sorry I can't recall where I read it) I know several working mothers who are still nursing (as you all do) and their children do benefit a lot from the ungoing nursing relationship; both from the immunological elements and the closeness it provides. Christine Gauthier LLL