Most lactation consultants encourage women to use common sense here. Think about the sandwich you had for lunch. If you only ate half, you might refrigerate it and have the rest for dinner, but you probably wouldn't want to eat it for lunch the next day. The same goes for breast milk. If after feeding your baby, you're left with half or a quarter of a bottle, put it in the fridge and offer it again at the next feeding, but that's it. "Used" breast milk can become contaminated, since bacteria from the baby's mouth can get into the bottle while your baby sucks. So it's best to either use the milk before bacteria have a chance to grow or toss it. We know it can frustrating to pour hard-pumped breast milk down the drain, but in this case, it's best for your baby's health. If your infant consistently leaves a certain amount of milk behind, start putting a little less in her bottle at the start of each feeding (you can always offer seconds if she seems to want more). This will prevent unnecessary waste and help you conserve your milk for later feedings.
Copyright 2009 Meredith Corporation.