Whether you're a new mom or a seasoned parenting pro,
often comes with its fair share of questions. Here are answers to
some common inquiries that mothers - new and veteran - may
How do I store my breast milk?
You can freeze and/or refrigerate your pumped (or expressed)
breast milk. It's important, though, to store it in clean and
sterile bottles with screw caps, hard plastic cups that have tight
caps, or nursing bags (pre-sterilized bags meant for breast milk).
Also make sure to put a label on each indicating when the milk was
pumped. You should not add fresh milk to milk that is already
How long, exactly, can I store my breast milk?
For healthy full-term infants:
- You can store it at
- for 4 to 8 hours (at no warmer than 77Âº Fahrenheit, or 25Âº
- You can store it in the
- for up to 2 to 3 days at 32Âº-39Âº Fahrenheit (0Âº-3.9Âº
- 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
- for up to 2 weeks in a freezer compartment located
- for 3 to 4 months in a freezer that's self-contained
and connected on top of or on the side of the refrigerator and
is kept at 0Âº Fahrenheit (-18Âº Celsius). But be sure to store
the milk in the back of the freezer,
in the door)
- for 6 to 12 months in a deep freezer that's always 4Âº
Fahrenheit (-20Âº Celsius)
If you thaw frozen milk, you can refrigerate it and use it
within 24 hours, but do
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,
in the freezer. Talk to your doctor if you have any concerns or
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
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.
My frozen breast milk changed color. Is this OK?
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
How do I clean 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 5 to 10 minutes. Check
the manufacturer's recommendations for the length of time to
boil the parts. (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) after 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
microwave them. Instead, you can run the bottle or freezer bag
under warm water for a little bit, swirl the bag or
bottle 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.
Larissa Hirsch, MD
Date reviewed: May 2008
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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