Storage and Handling of Breastmilk
Mothers who are pumping breastmilk for their infants should store the milk in the cleanest and safest way. It can be stored in any clean container: plastic, glass or nurser bags. Recommendations for storage temperatures and times vary greatly from one authority to another. We are recommending guidelines based on research and common sense.
Freshly pumped breastmilk can be kept at room temperature for 4 hours. If it will need to be kept longer, please refrigerate. Milk that has been previously chilled should be kept at room temperature for no longer than an hour or so.
Breastmilk may be stored in a refrigerator 4-8 days. If you think that you may not use it within that time period, freeze it. If you find you have milk that has almost reached its expiration date in the refrigerator, you may freeze it for later use.
Breastmilk may be stored in a freezer for up to 3 months and in a deep freeze for up to 12 months. The freezer is cold enough if it keeps your ice cream solid. That will be about 0° For -20° C. It should be placed in a part of the freezer that will not be subject to changes in temperature as the door is opened and closed. If plastic nurser bags are used, they should be doubled or protected from being bumped and torn in the freezer.
You may add “new” milk to previously chilled or frozen milk. Chill the “new” milk prior to adding it to the container of milk. The expiration date of that container of milk will be from the date of the original milk.
It is best to freeze milk in feeding-sized quantities. If you are just starting to pump, you may not yet have an idea of what will be the right size for your baby. Freeze in 2-3 oz quantities to start. You don’t want to thaw out more milk than your baby will take in 24 hours. You can always get more if necessary, but you will be dismayed if you have to discard pumped breastmilk. After you have some experience with how much your baby takes from a bottle, you can freeze milk in that quantity.
Breastmilk can be thawed in lukewarm water in just a few minutes. Then it can be warmed to serving temperature in the same manner. Never make it warmer than body temperature. Never use a microwave to thaw or warm breastmilk. Discard any milk left in a bottle after a feeding. Thawed breastmilk must be discarded after 24 hours. Do not re-freeze it.
Chill any milk that you pump at work either in a refrigerator or a portable cooler bag. A cooler bag can be used to transport the milk home.