Now that I'm no longer NAKing, one more thing I wanted to add. I dealt with excess lipase in my milk. This is not harmful but basically the upshot is that milk that has been frozen for more than 2-3 weeks tastes really yucky and my daughter wouldn't drink it. The solution I discovered is to scald the milk before freezing it, and after I do this it's fine. This problem isn't really common, but it does happen and I'd hate for somebody else to be blindsided by it. So I think it's important to pump enough in advance that you can let some milk sit in the freezer, thaw it a month later, and see if it's still good. If it's not, you then have time to adjust and you aren't faced with going back to work leaving your child with a freezer full of milk they won't touch. So I would recommend you pump at least a couple times 6-8 weeks before your return to work, freeze it, and then check in a month to see if it is still palatable.
Kellymom.com has more information about excess lipase.
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