Building up a great freezer stash of breast milk is a dream for many pumping moms but eventually, you'll have to know how to defrost frozen breast milk. Whether you're doing it to make a bottle for daycare, to give yourself a night off from breastfeeding, or to make baby food, there's definitely a proper way to thaw your breast milk.

The important thing to remember is that like any other type of food item, dairy or otherwise, breast milk can spoil. According to Medela, the absolute best way to defrost frozen breast milk is to place the milk in the fridge overnight. This option will not only thaw the milk, but will also preserve the components and nutrients of it.

But hey, if you haven't woken up in a rush on a Tuesday morning and realized you didn't put any breast milk in the fridge, then I'm not sure if you and I can be friends. In a pinch, you can thaw breast milk as soon as you pull it out of the freezer. KellyMom suggested holding the frozen breast milk under running water, starting off at a cool temperature and slowly increasing the warmth of the water. The Mayo Clinic also recommended placing the frozen breast milk in a container of warm water to defrost it.


No matter which option you choose, make sure you never microwave your breast milk or put it in boiling water to thaw. According to Medela, this type of defrosting can cause vitamin and mineral loss in the breast milk. And because breast milk can go bad, KellyMom does not recommend thawing breast milk by leaving it out at room temperature.

Remember, no matter how much breast milk you thaw, it's best to toss it after 24 hours according to the Mayo Clinic. You can't refreeze thawed breast milk, so make sure to defrost the amount you'll actually need and use.