Noreen Stonor Drexel Birthing Center
Newport Hospital

Storing, Warming and Thawing Breast Milk

newborn infant

If you decide to express your breast milk (manually or with a pump), it's important to learn about proper storage of breast milk. First, be sure you have clean containers for storing your milk. Discuss whether you should use glass or plastic containers with your lactation consultant. Always label and date the container and refrigerate or freeze the milk immediately.

Breast milk can be safely stored in a refrigerator for five to seven days. The milk should be stored in the coldest part of the refrigerator, never in the door of the refrigerator.

If you plan to freeze breast milk, be sure to freeze it within 24 hours of pumping. If not frozen immediately, the milk should be kept in a refrigerator for the 24 hours prior to freezing. Breast milk can be stored in a freezer for three to four months; store the milk in the back of the freezer, not in the freezer's door. Unopened, thawed breast milk can be safely stored in a refrigerator for 24 hours. Never refreeze breast milk.

To minimize waste, it may be best to store breast milk in two- to four-ounce amounts. You can purchase breast milk storage bags that easily allow you to measure the amount of milk you are storing.

Warming and thawing breast milk

To warm or thaw stored breast milk, run the container under warm tap water or immerse the container in a bowl of warm water. Never microwave or boil breast milk, which both heat the milk unevenly and can cause hot spots in the milk that could burn your baby's mouth and throat. In addition, heating in a microwave or boiling breast milk can harm the protein and antibody composition of the milk.

After thawing breast milk, roll the bottle between your hands to evenly distribute the consistency of the milk.

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