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Storing Breastmilk

It is important to store your breastmilk in a place that is sanitary and safe. If you are pumping and storing your breastmilk at work in a common refrigerator, make sure you label it with your name or put it in a bag so it is not mistaken for regular milk.

If you have any questions about proper storage of breastmilk, talk to your pediatrician, International Certified Lactation Consultant or follow the guidelines below from La Leche League International.

Breastmilk Storage Guidelines
Where	Temperature	Time
At room temperature (fresh milk)	66° to 78°F (19° to 26°C)	4 hours (ideal) up to 6 hours (acceptable)* (Some sources use 8 hours)
In a refrigerator	<39°F (<4°C)	72 hours (ideal) up to 8 days (acceptable)**
In a freezer	-0.4° to -4°F (-18° to -20°C)	6 months (ideal) up to 12 months (acceptable)
* The preference is to refrigerate or chill milk right after it is expressed. ** Eight days is acceptable, ideally collected in a very clean, careful way.

What Type of Container to Use

Refrigerated or frozen milk may be stored in:

• Hard-sided plastic or glass containers with well-fitting tops.
• BPA Free containers, like Lansinoh Breastmilk Storage Bottles.
• Freezer milk bags that are designed for storing breastmilk, like Lansinoh Breastmilk Storage Bags.

Other storages tips:

• Containers should not be filled to the top - leave an inch of space to allow the milk to expand as it freezes.
• Disposable bottle liners are not recommended. With these, the risk of contamination is greater. These types of bags tend to be less durable and tend to leak, and some types of plastic that is used to make these bags may destroy nutrients in milk.
• Mark the date on the storage container. Include your baby's name on the label if your baby is in a day care setting.
• Keep frozen milk in the middle of the freezer away from the sides where the temperature can fluctuate as you do not want milk to partially thaw as thawed milk cannot be refrozen.

How to Warm the Breastmilk

• Thaw and/or heat under warm, running water.
• Do not bring temperature of milk to boiling point.
• Gently swirl milk before testing the temperature. Swirling will also redistribute the cream into the milk. (It is normal for stored milk to separate into a cream and milk layer.) Do not shake vigorously as it could damage some of the live components of breastmilk.
• Do not use a microwave oven to heat breastmilk.

Thawed Breastmilk

• Previously frozen milk that has been thawed can be kept in the refrigerator for up to 24 hours.
• It should not be refrozen.

Has Your Frozen Breastmilk Gone Bad?

In very rare cases, some mothers who have meticulously expressed and frozen their milk for later use have discovered to their dismay that all their frozen milk has turned rancid. This happens when a mother produces milk that is high in lipase, the enzyme that breaks down fat in the milk. Depending upon the level of lipase in her milk, some mothers notice this rancid smell after their milk has cooled in the refrigerator; others, notice it only after the milk has been frozen for a while. Thankfully this doesn't happen often, and this can be prevented if the lipase is detected before the milk is frozen.

It is suggested that every mother who is planning to freeze her milk should freeze some test batches of milk and thaw it out after a week or so to be sure it has not become rancid. If it smells rancid, she may need to scald the milk before freezing in the future to deactivate the lipase in her milk. For more information, please see the Breastfeeding Answer Book published by La Leche League International.