Step-by-step Guide to Collect, Store, Freeze and Thaw Breast Milk

Whether you’re planning to stock up your freezer with pumped milk in order to get back to work or just to have some extra in reserve ready to free you for the night out with your girls, follow these easy steps to pump or hand express your breast milk, safely store and thaw it.

Step 1. Choose Your Storage Equipment

Before expressing breast milk you need to choose your storage equipment wisely. It all comes down to how long you’re planning to let your milk sit in the fridge or freezer. Some containers are better for freezing only because they allow you to store them flat, thus saving more space. They are also made safe from leaking. 

When you decide which container suits you best, make sure to check that it’s BPA free and safe for food storage. 

My Top Picks for Storage Containers

1. Lansinoh Breastmilk Storage Bags With Convenient Pour Spout Double Zipper Seal (Best of the best so far!)
2. Dr. Brown’s Breastmilk Storage Bags (Simple, easy to fill & use)
3. Medela Breast Milk Storage Bags (Best price!)
4. Kiinde Twist Pouch Direct-Pump Direct-Feed Breast Milk Storage Bags (Best choice for traveling)
5. Milkies Pre-Sealed & Ready to Use Plastic Bags for Storing & Freezing Breast Milk (freeze flat, easy to store, no leakage)

Here are my top picks for plastic bottles.

My Top Picks for Milk Storage Organizers

1. Breastflow Milk Storage Organizer
2. Kiinde Baby Food Pouch Organizer
3. mDesign Storage Organizer Container Bin

Step 2. Gather Your Equipment

If you’re pumping your breast milk, you need to first clean and dry all the parts to prevent any contamination of breast milk with bacteria. Then assemble them. If you’re hand-expressing, all you need is a clean storage bag. You may need an extra collecting container if you use a pump to express breast milk for storage.

Step 3. Wash Your Hands

Your hands should be cristal clean when you start expressing breast milk. Use a soap to wash your hands or an alcohol-based hand sanitizer if you don’t have water and soap available. The hand sanitizer should contain at least 60% of alcohol.

Step 4. Pump or Hand Express Your Breast Milk 

• Get relaxed. Sit in a comfortable position. 
• Take some deep breaths. Think about something pleasant. 
• Try a soft breast massage before you start expressing. This will encourage a letdown. 
• Picture your baby (or put his/her actual picture in front of you). This will help with the production of oxytocin which lets the milk out of your nipple. 
• If you pump, you may find it helpful to create a good seal by moistening the flange with water.
• Pump around 10 minutes on each side.
• Do not fill up the container to the top. Breast milk needs space to expand as it freezes. Aim for filling ⅔ of the storage container.

Step 5. Seal the Container

 Sealing your container securely will prevent leaking. Use tight fitting lids for glass or plastic bottles. Do not use nipples as caps if you are freezing breast milk.

Step 6. Store Breast Milk After Expressing

Label collected breast milk with a date and time of expressing. Put it in the freezer as soon as possible.

• Storing your breast milk at the door of the refrigerator is not a good idea. The changes of the temperature when opening and closing the fridge may affect the quality of milk.
• If you are not going to use expressed breast milk within 3 days, freeze it right after collecting. 
• Breast milk can be stored in the freezer inside the refrigerator for up to two weeks.
• If you’re using a separate freezer which is a part of the refrigerator (but has a separate door to it, collected breast milk can be stored for up to 6 months there. Make sure to store it deep enough.
• In case of using a stand-alone freezer, breast milk can be stored there for up to a year. 
• If you need to travel and take pumped breast milk with you, use an insulated cooler with frozen ice packs. 24 hours is the limit. After you get to the destination, use the milk immediately, put it in the freezer if you’re planning to use it within three days, or simply freeze it. 

Milk Storage Guidelines

Safe Thawing of Breast Milk

1. Remember, over time breast milk quality may decrease, so thaw the oldest pumped milk first. 
2. How to thaw breast milk: in the fridge overnight; in a container with a lukewarm water; under running water.
3. Do not use microwave to thaw thaw milk. First of all, it’s unsafe. This type of thawing ends up in destroyed nutrients in breast milk. On top of that, heating breast milk in microwave can lead to uneven temperature of milk with some spots of very hot liquid which may lead to burning the baby’s mouth.
4. If you thaw breast milk in the fridge, keep in mind, it is only good for 24 hours. Start counting this time when the milk is completely thawed.
5. Once you take the milk out of the fridge or let it sit in the water until completely thawed, use this milk within 2 hours.
6. Never freeze thawed breast milk again.