What do I need to know about storing breast milk?

November 30, 2023 / Birth Center / 4-minute read

As a new mother, sometimes you may find yourself pumping breast milk for a few feedings during the day to help ease the strain on you, especially when you return to work. Proper breast milk storage ensures you don’t waste your milk. This blog post will discuss everything you need to know about storing breast milk.

The basics of storing breast milk

When you pump breast milk, store it in a clean, dry container. Breast milk storage bags are pre-sterilized, reducing the risk of contamination. They’re also free from BPH, durable, leak-proof, and built to protect the nutritional content of breast milk during storage. Before storing your milk, date and label each bag’s contents with the date and time pumped. It is essential to note that breast milk is safe at room temperature for up to four hours. Once refrigerated or frozen, breast milk should be used within specific guidelines.

Updated recommendations for storing breast milk

The Centers for Disease Control recently updated their recommendations on breast milk storage. Previously, many people followed the 5-5-5 rule: storing breast milk for five hours at room temperature, five days in the refrigerator, and five months in the freezer. While the new guidelines may require a bit more effort to remember, they now allow for the safe storage of breast milk in the freezer for up to 12 months. This extended storage time enables some infants to continue benefiting from the nutritional advantages of breast milk for a longer duration, promoting their overall health and well-being.

These guidelines provide a general reference for storing human milk at different temperatures. It is important to consider various factors that can impact the safe storage duration, such as milk volume, room temperature during expression, temperature fluctuations in the refrigerator and freezer, and the cleanliness of the environment.

	Storage Location and Temperatures
Type of Breast Milk	Countertop 77°F (25°C) or colder (room temperature)	Refrigerator 40°F (4°C)	Freezer 0°F (-18°C) or colder
Freshly Expressed or Pumped	Up to 4 Hours	Up to 4 Days	Within 6 months is best Up to 12 months is acceptable
Thawed, Previously Frozen	1–2 Hours	Up to 1 Day (24 hours)	NEVER refreeze human milk after it has been thawed
Leftover from a Feeding (baby did not finish the bottle)	Use within 2 hours after the baby is finished feeding

These guidelines are for healthy full-term babies and may vary for premature or sick babies.

Download this handy milk storage chart for the front of your refrigerator. For more information, download the CDC quick reference guide to storage and preparation of breast milk.

Refrigerated breast milk

Refrigerated breast milk can be stored at 40 degrees Fahrenheit for up to four days.
If you want to store breast milk beyond that time, it’s best to freeze it.
When removing breast milk from the refrigerator, don’t heat it on the stove or in the microwave. Instead, place it in warm water to raise its temperature gently.
Never refreeze breast milk once it has been thawed.

Frozen breast milk

Frozen breast milk can be stored in the freezer for up to 12 months, but for the best quality, it should be used by the six-month mark.
Store it in the back of the freezer to protect it from temperature changes.
Thaw frozen breast milk slowly by placing it in the refrigerator or a bowl of warm water.
Use the breast milk within 24 hours of thawing.

Transportation and storage tips

If you need to transport breast milk through a car, place it in a cooler with ice packs or a frozen gel pack.
Once you reach your destination, place the container in the refrigerator or freezer as soon as possible.
If you plan to be away from home for an extended period, make sure you have access to a refrigerator or a way to safely store your milk.

Signs of spoiled breast milk

Breast milk that has gone bad will have an off smell or taste and appear differently than freshly expressed breast milk. It may have a clumpy or grainy texture or tiny white specks floating in it. If you think your breast milk is spoiled, do not use it. Instead, dispose of it and pump a fresh supply.

Storing breast milk is crucial to ensure that your baby is getting the proper nutrition and that you are not wasting your hard-earned efforts. Remember to store your breast milk correctly, label and date it, refrigerate or freeze it based on the guidelines, and always check to ensure that it’s not spoiled before feeding it to your baby. These steps will help keep your breast milk safe and fresh for your little one.