Pumping breast milk is a labor of love. Whether you’re preparing for a return to work or simply want a stash for later, knowing how to store your liquid gold safely is important l for your baby’s health. Resources found on our “Milk Hub” provide clear, expert-backed advice to help you handle and store breast milk with confidence.
What Kind of Containers Should I Use?
Your breast milk should be stored in a way that keeps it clean and safe. You can use BPA-free plastic or glass containers with tight-fitting lids, or special bags designed for storing breast milk. Whatever you choose, make sure it’s clean before you use it.
How Long Can Breast Milk Be Stored?
Storage times can feel confusing, but following these research-based guidelines will ensure your milk remains safe for your little one. These recommendations from the Centers for Disease Control and Prevention (CDC) are for healthy, full-term infants.
At Room Temperature
Freshly expressed breast milk can be kept at room temperature (up to 77°F or 25°C) for up to 4 hours. If you don’t plan to use it within this time, it’s best to refrigerate it right away. If your milk was previously chilled, try to use it within two hours of it being at room temperature.
In the Refrigerator
You can store breast milk in the refrigerator (at 40°F or 4°C) for up to 4 days. The World Health Organization (WHO) suggests storing it at the back of the fridge where the temperature is most stable, away from the door. If you don’t think you’ll use the milk within four days, freezing it is the best option.
In the Freezer
For longer storage, the freezer is your best friend. Breast milk can be stored:
- In a standard freezer (at 0°F or -18°C) for up to 6 months for best quality, though the CDC notes up to 12 months is acceptable.
- In a deep freezer or chest freezer for up to 12 months.
To protect your milk, store it in the back of the freezer where the temperature is coldest and won’t be affected by the door opening and closing. If you’re using freezer bags, consider double-bagging or placing them in a hard container to prevent tears.
Tips for Freezing and Combining Milk
- Freeze in Small Batches: It’s a good idea to freeze milk in small, feeding-sized amounts, like 2 to 4 ounces. This minimizes waste, as you won’t have to thaw more than your baby will drink. You can always thaw more if needed.
How to Thaw and Warm Breast Milk Safely
To safely thaw your stored milk, follow these steps:
- Thaw in the Refrigerator: The safest method is to let the milk gradually thaw overnight in the refrigerator.
- Use Warm Water: If you need a faster option, gently warm the container by holding it under lukewarm running water or placing it in a bowl of warm water.
- Avoid the Microwave: Never use a microwave to thaw breast milk. It can create uneven hot spots that may burn your baby’s mouth and destroy essential nutrients.
Once thawed, the milk can be served at room temperature or warmed up. Remember to swirl the milk gently to mix the fat, which may have separated.
Using Thawed Milk
- Time Limit: Once breast milk is brought to room temperature or warmed, use it within 2 hours.
- 24-Hour Rule: If milk is thawed in the refrigerator, it must be used within 24 hours.
- Do Not Refreeze: Never refreeze breast milk after it has been thawed.
- Discard Leftovers: Any milk left in the bottle after a feeding should be discarded.
Transporting Your Breast Milk
If you’re pumping at work or out and about, using an insulated cooler bag with ice packs is key to keep your milk chilled. This will keep it safe until you can get it home to your refrigerator or freezer.