Best Methods for Breast Milk Storage

March 8, 2023

breast milk bottlesAre you pumping and storing breast milk? That’s great! It ensures your baby has access to the highest-quality food they can get, even when you’re not around.

Pumping and storing breast milk also gives your partner, other family members, friends, and other caregivers a special way to bond with your baby – because we all love the hands that feed us, right?

Breastmilk is Perishable, so Attentiveness Pays Off

The thing is, all that perfect breast-produced food – complete with probiotics, antibodies, fat, hydration, nutrients, etc. – is also perishable. So paying attention to storage details pays off, ensuring your baby always drinks fresh, unspoiled, and uncontaminated boob juice.

Here are the ways you can ensure that breast milk contains all the good stuff – and none of the bad stuff.

Always sterilize the equipment

This isn’t something to overlook. Fortunately, most bottles and breast pump equipment are dishwasher safe these days, making it easy to sanitize them. However, read all of the instructions and cleansing/sterilization instructions that come with the pump, bottles, and other related equipment to be safe.

This does not mean everything has to be boiled; in most cases, a thorough wash with warm/hot water and soap – and a thorough dry – is all required.

Use clean hands and breast milk containers

Do wash your hands before pumping, and ensure the containers you’re pumping into are also clean.

Adhere to the CDC Breast Milk Storage Guidelines

The CDC has a quick and easy Storage Duration for Fresh Human Milk…Chart with all the information you need. We recommend printing it out and hanging it on the fridge when you need to refresh your memory.

The basic guidelines for storing milk, based on fresh, refrigerated, or frozen, are:

Room temperature

Breast milk that is covered immediately and stored on a countertop or table will remain good for 6 – 8 hours, after which it should be thrown out.


Sealed, refrigerated breast milk should last for about five days, after which it should be dumped. Store it towards the back of the fridge, rather than in the door, so the temperature remains cooler and more consistent.

Insulated cooler bag

If you move refrigerated/frozen milk into an insulated cooler bag with freeze packs, it should be good for 24 hours. Minimize the number of times the bag is open, and keep milk containers in direct contact with freezer packs.

Refrigerator freezer compartment

Breast milk stored in the freezer compartment of your refrigerator will remain good for 3- to 6 months. Again, the back of the freezer provides the most consistent temperatures.

Upright or chest-style deep freeze

If you want a breast milk supply that lasts longer than six months, invest in a chest- or deep upright freezer, which will remain good for 6- to 12 months.

It’s not easy to throw away breast milk past its deadline – but it’s worth knowing it’s not contaminated. And we have plenty of patients who take “just about to expire” breast milk and use it in baking and dinner recipes that call for milk. Why not?

Tips for Healthy Breastmilk Thawing

Just a few more tips if you use frozen breast milk:

  • It’s best when thawed in the fridge and then brought to room temperature or quick-thawed in a warm water bath.
  • Never microwave breast milk, as this can create dangerous “hot pockets” that burn a baby’s mouth, and there is always a chance that microwaving changes the molecular makeup of the milk.
  • Never re-freeze breast milk that has been thawed. Switch it into the fridge or throw it out.
  • Never add fresh breast milk to frozen breast milk.

Interested in working with a women’s-only obstetrician to prioritize your well-being and breastfeeding success? Schedule an appointment with Women’s Healthcare Associates.