Everything you need to know to safely store and serve breast milk to your growing baby
The early days of motherhood are overwhelming. You’re always exhausted, and sometimes you need a break to relax or catch up on some much-needed sleep. This can be especially true for mothers who are breastfeeding.
According to the Centers for Disease Control and Prevention (CDC), over 81% of new moms start breastfeeding their babies at birth, with around 51% continuing for 6 months and around 30% continuing for the first 12 months.
If you’re a breastfeeding mother, getting the rest you need may require you to turn the job of feeding your newborn over to somebody else. This means you’ll need to know how to pump and store your extra breast milk safely.
This guide will answer all of your questions about breast milk storage so you can keep your baby well-fed, healthy and safe.
Start with clean hands and equipment
Before pumping breast milk, wash your hands and make sure all of the equipment you’re using is properly sterilized (pump pieces, bottles, nipples, etc.). The easiest way to sterilize your equipment is to use hot soapy water. This should kill all the bacteria that could make your baby sick.
What containers can I use for storing breast milk?
Breast milk can be stored in hard-sided plastic or glass containers with tight-fitting tops or plastic bags that are made for storing breast milk.
Tips for storing breast milk in bags
- When storing breast milk in bags, make sure you are extra careful because sometimes bags can tear or puncture.
- If freezing breast milk, be sure you leave room at the top of the container or bag you’re using because breast milk will expand in the freezer.
- Label the bag you’re using with the date and your baby’s name, especially if you’ll be sending the breast milk with your baby to daycare.
What containers shouldn’t I use to store breast milk?
Freshly expressed milk should never be stored in disposable bottle liners or plastic bags since neither is designed explicitly for breast milk storage.
How much breast milk do I need to store to meet my baby’s needs?
It’s recommended that you store 2 to 4 ounces of breast milk in recommended containers to meet the needs of a baby 6 weeks old and older. It’s also a good idea to store containers of 1 to 2 ounces of milk for babies less than 6 weeks old or for an older baby who is extra hungry.
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How long does breast milk last?
Breast milk has different shelf lives depending on how it’s stored:
- Room temperature. Under ideal conditions, breast milk can be left at room temperature for 6 hours, but it’s best to refrigerate/freeze it within 4 hours, especially if the room is warm.
- Insulated cooler. You can store breast milk in an insulated cooler with ice for up to 1 day.
- Refrigerator. Breast milk is best if used within 4 days if stored in the refrigerator, but it can be used for up to 5 days. Make sure to store your breast milk at the back of the refrigerator where it’s coldest.
- Freezer. Frozen breast milk can be used for up to 12 months, but it’s best to use it within 6 months. Store your breast milk at the back or bottom of your freezer when possible.
Does the room temperature affect how long I can leave breast milk on the counter before using it?
Yes, the recommended time for keeping breast milk at room temperature does depend on the temperature of the room. If the room temperature is 77 degrees Fahrenheit or lower, it’s advisable to use the breast milk within 4 hours. Temperatures above 77 degrees will cause the milk to spoil even quicker.
In most instances, the milk should be safe to use for up to 2 hours without putting it back in the refrigerator if your baby doesn’t consume the entire amount during one feeding.
Can I reuse breast milk leftover from a feeding?
Once your baby has finished feeding, any remaining breast milk in the bottle can still be used within a 2-hour timeframe. However, it’s important to discard the leftover breast milk after 2 hours to ensure its freshness and safety. To minimize waste, you may want to consider storing and thawing breast milk in smaller quantities.
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How do I thaw breast milk?
The easiest way to thaw breast milk is to place it in the refrigerator overnight. You can also place it under warm running water or in a bowl with warm water.
Do storage recommendations change if I move my breast milk from a deep freezer to a kitchen freezer or vice versa?
Moving breast milk from a kitchen to a chest freezer and vice versa doesn’t affect breast milk quality or storage recommendations. This is because both freezers are typically set to 0 degrees Fahrenheit (or colder), and milk is safe to store at this temperature for up to 12 months, although it’s optimal to use it within 6 months.
Can I freeze unused breast milk after storing it in the refrigerator for a few days?
It’s fine to move freshly expressed or pumped breast milk from a refrigerator to the freezer to help keep it fresh longer as long as it hasn’t been in the refrigerator for more than 4 days. After 4 days, the milk can start to develop harmful bacteria and should not be used unless it’s been frozen.
Can I combine freshly expressed breast milk with breast milk from my refrigerator or freezer?
It’s best not to combine freshly expressed milk with milk previously cooled in a fridge or freezer. Doing so can rewarm older milk and ruin the quality of both the new and old milk. However, you can combine them if you cool the expressed milk first.
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How long will frozen breast milk keep in the freezer if the power goes out?
Since most full freezers can keep a freezer full of food safe for about 48 hours without electricity if they’re not opened (or 24 hours when they’re half full), breast milk should still be safe to use and, therefore, doesn’t have to be thrown away.
That said, you should inspect the breast milk once the power is restored. If the milk has started to thaw but is still partially frozen, it can be refrozen. If the milk has thawed but is still cold, it should be moved to the refrigerator and used within 24 hours.
What color should frozen breast milk be?
Breast milk can vary in color depending on what a woman eats or drinks and whether or not she’s taking medication. Stored breast milk will typically separate into 2 layers, a cream layer and a milk layer, and can take on any of the following tints in addition to white:
- Green
- Yellow-orange
- Pink
- Yellow
- Blue
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How can I safely store breast milk while traveling?
When traveling, you should store breast milk in an insulated cooler bag with ice packs. Doing so helps keep the milk frozen for up to 24 hours. If the milk is still frozen when you reach your destination, you can transport it to a freezer and continue to store it until ready to use.
Can breast milk go bad?
Yes, breast milk can go bad. Spoiled breast milk will smell bad, just like regular milk does. If in doubt, it’s best to throw it out.
For more detailed information on storing and handling breast milk, see Le Leche League’s Guidelines for Storing Pumped Milk.
For more questions about breastfeeding, contact All About Women to talk to a medical professional – or visit our Knowledge Center to read articles like:
