K.K.
I would sterlize the bottles. It made me feel better too. I don't like to wash bottles in the dishwasher, because sometimes "stuff" gets on them and I have to rewash them again. Plus, it is not like they take them much longer to sterlize and they are done in about five minutes and you don't have to wait until a full load is in the dishwasher. I only used glass bottles and sterlized them every time I used them. Just wash out the old sterlizer, then run in through with no bottles in it with the water added and it will clean in all out. Good luck and Congrats!
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