The Safe Way to Freeze Breast Milk


When I was pregnant with my son more than six years ago, the green baby movement was just beginning.  I had no idea about the dangers of plastic, so I stocked up on plastic baby bottles and plastic breast milk storage bottles.  Eventually I switched most of them out for the newer BPA-free options that began to come out, but now that I’m pregnant again and much wiser, I’m using glass all the way!

By now, you have all probably heard about the dangers of BPA in plastic.  BPA, or Bisphenol-A, has been linked to disruptions in the endocrine, reproductive and cardiovascular systems as well as early puberty, obesity, resistance to chemotherapy and more.  BPA is banned in baby bottles and cups in the European Union, Canada and China.  And just recently, the FDA agreed to ban BPA in baby bottles and sippy cups, although they were reluctant to do so.

The alternatives to BPA in baby bottles are plentiful.  But still most of are composed of plastic which, even without the BPA, is not the safest material to use especially if you are going to freeze or microwave it.  Plastics are usually made from crude oil and can contain other toxins such as phthalates that can leach into your food and drink.  This leaching process is accelerated when the plastic is frozen or heated.

The safest option for you and your baby is to store food and drink in glass containers.  Unfortunately, most of the glass baby bottles on the market today (and there are quite a few of them now) are not labeled as freezer safe.  What this means is that there is a chance that the bottle could break if you put it in the freezer with any sort of liquid inside.  It also means that the bottle could break if you attempt to transfer it directly from the freezer to the microwave.  Lifefactory’s glass baby bottles are the only brand that I have found that that claims to be freezer-safe and also safe to transfer directly from the freezer into boiling water.

If you don’t have the money to spend at least ten dollars each on freezer-safe glass baby bottles, there are cheaper alternatives:

1. Freeze in Ice Cube Trays and Transfer to Larger Containers

One great way to store breastmilk is to freeze it in ice cube trays and then transfer the frozen cubes to a larger glass container.  Again, you want to avoid using plastic ice cube trays.  So I plan to use either Green Sprouts Silicone Freezer Trays or Kinderville’s Little Bites Silicone Freezer Trays.  There are also stainless steel ice cube trays on the market but I don’t have any experience with using them.  Once the cubes are frozen, I plan to transfer them to large Pyrex bowls which are also freezer safe.  When you are ready to use the frozen breastmilk, just take out a few cubes and defrost them in the refrigerator or the microwave (again, in a glass container).  I am going to use the same method for freezing baby food.

2. Freeze in Individual Small Containers

Another alternative for freezing breastmilk is to freeze it in small containers that can easily be popped in the microwave or defrosted in the fridge.  Wean Green makes great little 4 oz. glass containers that can go straight from the freezer to the microwave.  These are especially useful if you plan to travel with them.  Or if you want to be really thrifty, you can freeze breast milk in 4 oz. Ball canning jars, which sell for less than $1 a piece.  These great containers can also be used for freezing baby food!

wean green glass baby food milk containers freeze breastmilk

If, like me, you have a stash of plastic baby bottles and cups left over from a previous child, don’t toss them out! is doing a BPA Bottle Buy Back program through August 31st!  You can $2 each in store credit for every plastic baby bottle or cup you send in to them – up to $50!

One thought on “The Safe Way to Freeze Breast Milk

Let Me Know What You Think!