Visit our Location
4535 Fanuel St, San Diego, CA
Give us a Call
(619) 374-8444

Simple Storage Guidelines for Breast Milk

-Storing and freezing in feeding size quantities can help to ensure you don’t waste much milk. You can always defrost more milk, but you can’t always use milk that has already been defrosted (more on that later). Make sure to leave a little room at the top of the container because the milk will slightly expand as it freezes. After all, you worked hard for that milk! Why waste it if you don’t have to?

-Always use fresh or newest milk first as it is higher in vitamins, protein, fat, antioxidants, probiotics, and immunoglobulins (which are basically magic little goblins that eat up germs so our body can get rid of them and keep us healthy).

-Breastmilk really is magical! The composition changes based on the time of the day so when possible try to use milk that was pumped at the same time of the day. For example, if it’s evening time and you’re choosing a bag to defrost, try to choose a bag that was pumped in the evening because it will contain nutrients meant for sleep! Morning milk is like a good ole’ cup-a-joe for baby, so give them milk that was pumped in the morning.

-Wanna know something else kinda rad? Your body changes the milk based on the baby’s cues. Such as the smell of their head and even the smell of their poop! Yeah! Poop! Your brain registers the smell of the poop and creates nutrients needed to best nourish them. Also, your nipple is a two-way valve and picks up the contents of their saliva and again releases nutrients, immunoglobulins, macronutrients, and micronutrients in response to what their body needs.

-Once the milk has been thawed use it within 24 hours. Frozen human milk that has been thawed for 24 hours should not be left out at room temperature for more than 2 hours. Do not refreeze milk that has already been defrosted.

-Freshly expressed warm milk should not be added to already cooled or frozen milk, to prevent rewarming of the already frozen milk. It is best to cool down the newly expressed milk first before adding it to older stored milk.

-Refrigerated and frozen human milk may have an odor different from fresh milk due to lipase-mediated triglyceride breakdown, releasing fatty acids. There is no evidence to suggest that infants will reject human milk due to this odor. Many foods that humans eat, such as eggs, cheese, and fish, have an unpleasant odor that does not affect the taste. (3) And who doesn’t love some stinky cheese?

-When you’re ready to defrost your frozen milk you can simply place the frozen bag into a lukewarm water bath (with the storage bag remaining sealed) and wait for the milk to come to room temperature. Gently swirl the milk to mix the creamy fat portion with the more watery portion.

-The milk does not need to be warm, in fact, lukewarm breastmilk has been shown to have higher fat content. Why? Because the fat in warmer milk adheres to the container. Cooler milk won’t stick to the bottle quite as easily.

-Do not microwave. It destroys nutrients and it’s really difficult to regulate the temperature.

-Didn’t use all the milk? No worries! Toss it in the bath for a milk bath to help ease skin and lessen any irritation.

-If your nipples are irritated, cracked, red, or sore try some nipples balm or creams. I also recommend hand expressing a drop of two of milk and leave it on your nipples to help that breast milk heal any wounds. Silverettes are also wonderful little silver cups to use and they help heal the tissue really well! Just let them stay attached to your nipples inside your bra or shirt while you’re not nursing.


Download Your Free Breast Milk Storage Guidelines

Dr. Steph’s Storage Guidelines

Save this guide on your phone or print it to always have on hand the best and safest ways to store and use your breast milk.

    We won't send you spam. Unsubscribe at any time.


    1) Breastfeeding and human lactation, 5th edition, Wambach and Riordan

    2) Lactation education resources

    3) Academy of Breastfeeding Medicine