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The 411 on Breastmilk Storage: How to safely store breast milk

With so much information out there on breastfeeding, it can be really confusing for new mothers to decide what is best for their babies. How to store human milk is one of the most frequently asked questions new mothers have. All mothers have situations in which they may need to store breast milk, especially working moms. Many working mothers return to work between six and eight weeks, a lucky few get three to four months leave with their new baby. Proper breastmilk storage is a top priority for most women. To cut out all the confusion, let’s go over some quick milk storage guidelines and tips.

Freshly expressed breastmilk storage

  • Can be stored between 4-6 hours at a room temperature ranging between 66-78 °F on a countertop or table. The cooler the room, the longer it will stay fresh.

  • In an insulated cooler with ice packs it can last up to 24 hours. The ice packs ideally should keep your milk between 5°-39°F. Using insulated coolers is a great way to store breastmilk at work and then transport it back home; it is simple and doesn’t require a lot of space or power.

Refrigerated breastmilk storage

  • You can store milk in a refrigerator between 3-7 days at any temperature below 39°F. At home make sure to keep it off the door and on a shelf in the back of refrigerator.

  • If you have a lot of space under your desk or in your office, consider buying a mini-fridge. You can store snacks, water, and your precious breast milk all in one place. That way if you accidently forget to take your milk cooler home with you, it’s no big deal, you will not lose an entire day of pumped milk and you can simply take it the next day.

  • A mini-fridge can be purchased for about $100 for a small 1.1 cubic model. They usually go on sale around mid- summer, just before college starts.

  • Ask HR about getting a mini fridge, most companies are fine with new mothers having one as long as it for storing your breastmilk.

Freezing Breastmilk

  • Most people have a refrigerator/freezer combo unit. Breast milk can last between 3-6 months in the back of the freezer if left as far from the door as you can get it and in the middle of a shelf. Three months is optimum.

  • Do not store it on the door of your unit whether you are freezing it or refrigerating your milk. Temperature fluctuates the most on doors and around them, so push it to the back!

  • In a separate deep freezer chest with a temperature below 0°F, breast milk can last up the twelve months but six months is best for freshness.

Thawed milk: how long is it good for after I thaw it

  • Never store thawed breast milk in a cooler or at room temperature.

  • It can be thawed overnight in the refrigerator and used within 24 hours.

  • Do not re-freeze it. Just like meat and other animal products, once it is completely thawed out human breast milk should be either used within 24 hours or discarded.

Frequently asked questions:

Can I add warm milk to thawed milk or frozen breastmilk? No, you should cool milk in the refrigerator first before adding it to thawed or frozen breastmilk.

What about freshly refrigerated milk, can I add warm milk to it? Common wisdom says no. Always cool your milk before adding it to any milk that is in the freezer or refrigerator.

How long can I leave breast milk out on the counter? Fresh breastmilk lasts up to 4-6 hours normally or 8 if room temperature is below 66°F. Do not ever leave thawed breastmilk on the counter. Feed it immediately after taking it out of the refrigerator.

Can I add different bags of breastmilk together? Yes, however it is actually better to store milk in smaller quantities and add them together for a feeding, than wasting one large bag of milk if your baby is not hungry. Label each bag with the date it was pumped and try to use bags pumped close together.

How much milk should I leave in each container when I pump? It is recommended that you store your milk in 1 – 4 oz. containers depending on your baby’s age. For example, if your baby is still a new born, it would be best to store your milk in 1 to 2 oz. bags or containers. If your child is older and feeds less, then 2 to 4 oz. might work better for you.

How do I reheat my breastmilk? Never use a microwave; it destroys a lot of the natural components in breastmilk. Breastmilk can be thawed out by running water over it and gently swirling it. The water should start out cool and gradually get warmer. For convenience, you can also use a bottle warmer. Frozen breast milk can be left in the refrigerator to thaw overnight or in about 12 hours

Should I shake my breast milk to get rid of the fatty cream that rises to the top of the bottle? NO, breastmilk should be gently swirled around to remix it. Vigorously shaking should always be avoided.

What container should I store my milk in? Glass or hard plastic BPH free bottles, bottle liners(double bag) or milk storage bags made especially for human milk. Any of these products can be purchased on line, at baby super stores, pharmacy chains, some local grocery stores and most big box stores.

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