You can store it at room temperature:
- for 4 to 8 hours (at no warmer than 77 degrees Fahrenheit, or 25 degrees Celsius)
You can store it in the refrigerator:
- for up to 8 days at 32 to 39 degrees Fahrenheit (0 to 3.9 degrees Celsius)
You can store it in the freezer (be sure to leave about an inch of space at the top of the container or bottle to allow for expansion of the milk when it freezes):
- for up to 2 weeks in a freezer compartment located inside the refrigerator
- for 3 to 4 months in a freezer that's self-contained and connected on top of or on the side of the refrigerator (but be sure to store the milk in the back of the freezer, not in the door)
- for 6 months or more in a deep freezer that's always 0 degrees Fahrenheit (-17.8 degrees Celsius)
If you thaw frozen milk, you can refrigerate it and use it within 24 hours, but do not refreeze it. And don't save milk from a bottle that your baby already drank out of.
It's also important to note that different resources provide different variations on the amount of time you can store breast milk at room temperature, in the refrigerator, and in the freezer. For example, the American Academy of Pediatrics (AAP) recommends using sealed and chilled milk within 24 hours and throwing out all milk that's been refrigerated for more than 72 hours. Talk to your child's doctor if you have any concerns or questions.
How much of my milk should I store in the freezer?
Although some women may choose to pump large volumes to be frozen, it's a good idea to actually store the breast milk in small portions so as not to waste any. Label the bottles, cups, or bags 2 oz. or 4 oz. (59.1 or 118.2 milliliters), then freeze them.
You could also pour the milk into ice cube trays that have been thoroughly cleaned in hot water, let them freeze until hard, store them in freezer bags, then count up the amount of cubes needed to make a full bottle.
Why does my refrigerated and frozen breast milk look weird?
Breast milk that's been frozen or refrigerated may look a little different from fresh breast milk, but that doesn't mean it's gone bad. It's normal for breast milk to look slightly blue, yellow, or brown when refrigerated or frozen. And it may separate into a creamy looking layer and a lighter, more milk-like layer.
How do I clean my breast milk bottles and pump parts?
You'll need to boil the nipples, bottles, and washable breast pump supplies (i.e., the breast shields and any other part that touches your breasts or your milk) for 10 minutes. (You also can sterilize them with a store-bought countertop or microwaveable sterilizer, but boiling works just as well and costs nothing.) Then you'll need to wash the bottle and pump supplies in hot, soapy water (or run them through the dishwasher) before every use after that. Bottles and nipples can transmit bacteria if they aren't cleaned properly.
Is it safe to microwave my baby's bottles?
The microwave can create dangerous "hot spots" in bottles of formula or breast milk, so you should never microwave them. Instead, you can run the bottle or freezer bag under warm water for a little bit, swirl it around in a bowl of warm water, or thaw the milk in the refrigerator. You can also put your baby's bottles in a pan of warm water (away from the heat of the stove) and then test the temperature by squirting a drop or two on the inside or your wrist before feeding your baby. You also can get bottle warmers for use at home or in the car.
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Growth and Development
What should you expect as your child grows? Learn how to understand and deal with your child's changing body and mind from infancy through the teen years.