• Breastfeeding
• Baby Health
• Lactation

How to Safely Store Breast Milk

By: Tori Bowlin

May 09, 2019

Breast milk. It's often referred to as liquid gold. And fortunately, it can be safely refrigerated or frozen for later use, which can allow you to be a bit more flexible in your new routine with baby.

Whether you're getting ready to return to work, planning for the chance date night out or just exclusively pumping, it's crucial to understand the guidelines for proper breast milk storage.

Storing Breast Milk

Use clean bottles with screw caps, hard plastic cups that have tight caps or nursing bags (pre-sterilized bags meant for breast milk). Be sure to label each container with the date the milk was pumped and your baby's name if the milk is going to childcare providers. You can add fresh, cooled milk to milk that is already frozen, but add no more than is already in the container. For example, if you have two ounces of frozen milk, then you can add up to two more ounces of cooled milk. For healthy full-term infants, milk can be stored as follows:

• Room temperature - six to eight hours (no warmer than 77°F, or 25°C).
• Refrigerator - up to five days at 32°-39°F (0°-3.9°C).
• Freezer– Varies depending on freezer type.
  • Up to two weeks in a freezer compartment located within the refrigerator.
  • Three to six months in a freezer that is self-contained (standard kitchen fridge/freezer combination) and kept at 0°F (-18°C). Breast milk should be stored in the back of the freezer and not in the door.
  • Six to 12 months in a deep freezer that is kept at -4°F (-20°C).
  • 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.

Thawing Breast Milk

Place frozen breast milk in the refrigerator to thaw (about 24 hours) then warm by running warm water over the bag or bottle of milk and use it within the next 24 hours. If you need it immediately, remove it from the freezer and run warm water over it until it's at room temperature. Never microwave breast milk and do not refreeze it. Once your baby has started to drink from the bottle, you should use it within one hour.

You may find that different resources provide different recommendations about the amount of time you can store breast milk at room temperature, in the refrigerator and in the freezer. Talk to your doctor or lactation consultant if you have any concerns or questions.