How To Thaw and Warm Frozen Breast Milk | 10+ Practical Tips to Know

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This is part of Breast Milk Storage and Handling series.
Other articles in this series:

1. How to Freeze Breast Milk | 10 Things You Need to Know
2. How to Thaw and Warm Frozen Breast Milk (this article!)
3. How to Rotate Your Breast Milk Stash

Even though thawing frozen breast milk seems like pretty straight forward, there are several things that can help you to better prepare breast milk for feeding and avoid wasting milk (who wants to waste breast milk, anyway).

Let’s just dive in!

1. Thawing for next day feeding:

Transfer the frozen breast milk from freezer to the chiller the night before (it can take 12 hours+ to thaw from a solid ice to slushy).

When it is close to feeding time, take the milk out and then put them on warm water for 10 minutes or until the milk feels warm (body temperature) to touch.
2. Thawing frozen breast milk in hurry:

Say, you forgot to transfer the milk to the chiller the night before.

It is still rock-solid in the morning when you are preparing for baby’s feeding.

The fastest way to thaw it is by putting it under a running water and gradually increase the water temperature.

You can also put the frozen milk inside a bowl of warm water, and change the water several times until the milk is fully thawed.
3. If you use breast milk bags, it is better to put the bag inside a ziplock bag before thawing or warming to catch any leaky milk.
4. An alternative way to thaw: you can use a bottle warmer to thaw and warm frozen breast milk simultaneously.

Yes, some bottle warmer can warm from the frozen state.

Some, like Kiinde, can even be used with breast milk bags directly.

Very time saving when you need to thaw and warm milk in a hurry.
5. If you don’t have access to warm water all the time (or a bottle warmer), I suggest you invest on a medium-size hot water thermos and fill it with hot water in the morning.

A good thermos will keep the water warm throughout the day, just enough for the purpose of warming your milk, and you don’t need to reheat water every single time.
6. Note that not all babies want warm milk, some are fine with the cold ones, you just need to test.

My baby personally loves warm milk, I guess because it resembles more like getting breast milk directly from mom =D.
7. Use the thawed milk 24 hours from the moment they are fully thawed (NOT from the moment you move it from freezer to fridge).

I wasted several bottles of milk not knowing about this, I thought the moment it is transferred to the fridge, it is considered thawed.

Wrong oh so wrong.

The 24 hours start from the moment your thawed milk do not have any ice / slushy texture in it.
8. Do not refreeze breast milk after it is fully thawed.
9. What if baby does not finish the milk?

There are several opinions:

• Some say discard right away because the milk has been mixed with baby’s saliva, and thus very prone to bacteria contamination.
• However, some say it’s okay to use the milk for the next feeding (not more than 1-2 hour apart) => see the article from Kellymom. Use your own judgment to decide. Your baby’s health, your comfort level, may vary.

10. It is normal if your breast milk separates into 2 distinct layers (creamy/fatty layer on top and watery/more transparent one below) after storing in the fridge or freezer.

Simply swirl the milk gently after warming breast milk to mix the layers evenly.

Do NOT shake the milk.
11. Thawed milk smells different from freshly pumped milk, which is normal.

But if it has a very strong smell to the point that your baby rejects it, you may have excess lipase issue.

You can try:

• mix your thawed milk with fresh milk and see if your baby would take this
• if your baby still rejects the milk, means you need to scald your milk prior to storing in the fridge/freezer. See this guide for scalding breast milk using a bottle warmer.

12. Do NOT heat or thaw your breast milk in a microwave or directly on the stove.

The milk may not warm evenly and contains hot spots. Additionally, rapid heating may affect the antibodies inside the milk.
13. Note: if you use breast milk storage bags a lot, exclusivepumping.com has a great no-waste guide on how to defrost breast milk bag (you just need to sign up for the newsletter).

I hope this little info helps you in understanding more the do’s and don’ts of how to thaw and warm frozen breast milk.

If you feel this is helpful, do share it with your friends.

Onto you!

Have you wasted some frozen milk by accident just like me? Share your story in the comment!