Breastfeeding + Pumping

How to Build a Breastmilk Freezer Stash

written by: Lo Mansfield, MSN, RN

I’m sure you’ve seen them – those pictures of freezers absolutely full of breastmilk, often called a “breastmilk freezer stash.” It’s impressive, staring at those rows and rows of tidily labeled bags – but it can also feel super overwhelming or paralyzing. Do we all really need that much frozen milk? What if we aren’t returning to work outside of the home? How about if we only work part time? Will your body doesn’t make that much extra? And how or when do we even start that process?

Do you need a breastmilk freezer stash?

Deep breath friend. Because you know what? You actually don’t need a freezer full of breastmilk before returning to work. And you don’t need a freezer full of breastmilk so you can be free to leave your little with sitters, run errands, or dream feed. We need to remember that ideally, we are always pumping when our baby is away from us and getting a bottle. And our bodies are smart! They continue to make what our littles need even when we are away from them. It is entirely possible to go back to work (and/or have some time away from your little) even if you don’t have a freezer full of milk at home.

What is a freezer stash of breastmilk?

These “stashes” of milk are extra milk (beyond the necessary nursing/pumping sessions) that has been pumped in the weeks leading up to a return to work (or planned times away from a little). Each day these bags of milk are pumped, labeled and frozen. They can then be pulled out when a bottle for the little is needed. If you are planning to bottle feed your little one at some point (and are currently exclusively nursing) it is recommended to introduce a bottle around 4 weeks of life.

Why would you need frozen breastmilk?

Alright, so even though we understand that a big breastmilk freezer stash isn’t actually necessary, we also know that many still work hard to have that extra milk in their freezers. Why are so many doing all of this extra pumping (often during their precious maternity leave) to fill that freezer?

Honestly? It depends! The reasons for wanting a stash can be pretty personal and individual. Of course, returning to work (outside of the home) is one of the most common reasons. Many are concerned that they won’t be able to pump as often as needed or generate as much milk as their little is consuming at home. A freezer stash can help fill in any gaps that occur between what they’re pumping at work and what is being used.

Other reasons you may want a little extra stash?

  • Dream feeds (for those who do not pump at this time)
  • Running errands
  • Date nights
  • Sitters + Nannies
  • Airplanes/Trips/Travel
  • Places they’d prefer not to breasfeed

Like we mentioned above, ideally one is always pumping when their little is away from them and getting a bottle (and that replaces the supply being used). Remember, we always want to be stimulating that supply and demand system. We can’t skip too many pumping sessions and not expect a change to our supply. But many find that there are the occasional times where you just can’t get that pumping session completed and the freezer stash at home ensures that there is milk for their baby.

How much milk should be in a freezer stash?

This too is going to depend on you and your (expected) needs. A loose calculation for basic breastmilk needs is that babies need about an ounce of milk for each hour they are away from their mothers. A typical bottle for a little in the first year is also about 4 ounces. But, you are going to have to learn what your little’s feeding patterns are! Then, you can consider what situations you want some milk stored in your freezer or times you may not be able to pump and replenish.

Are you discouraged because you only get an ounce or two when you pump? Hang on!

2 oz x 7 days/week x 8 weeks = 112 ounces (or 1 x 7 x 8 = 56 ounces)

112 ounces/4 ounces (a standard bottle size) = 28 bottles/feeds (or 56/4 = 14)

I know an ounce or two doesn’t seem like much on it’s own, but if you pump for these couple early months and get this output that is 14- 28 extra feedings for your little!

When should you start building a freezer stash?

Many are able to start collecting milk very early because of tools like the Haakaa or the Elvie Curve. These tools attach (via negative pressure/minimal suction) to the maternal breast that is not being nursed on during a feeding session and catch any milk that leaks during letdown(s). Most can begin using them and collecting in the first few days postpartum. Very, very rarely do these lead to oversupply issues, as they largely only collect what is leaking (but don’t actively pull milk from the breasts as an electric pump does). (If you already have a known oversupply issue, a tool like a Milkies or the Elvie Catch is a better choice, as these both collect milk without applying any negative pressure or suction).

Where do you add in a pumping session?

Ok, cool, but what about pumping, right? When should you start that? Whether or not you are pumping initially for supplementation, it is best to wait to start pumping for “extra” until about 4 weeks or so postpartum. This allows your milk to fully come in, to regulate, and for you and your little to establish a good rhythm, routine, and feeding relationship. If you feel that you don’t have a good relationship or routine at this point – it’s okay to hold off on pumping!

Most littles fall into a loose 3 hour feeding schedule in these early months. You may find that pumping about 30 minutes – 1 hour after a nursing session is good timing for both fitting in a pumping session and feeling that you have milk for your little one by the time they are awake and hungry again. Remember, your breasts are never actually empty. Keep “asking” in that pumping session. Your body can make enough for that AND for feeding your little at that next feed.

How many pumping sessions will you need?

Your needs, you schedule, and your supply will determine how often and when you’ll need to add in an extra pumping session. Your prolactin levels ARE highest in the mornings. So, you may want to take advantage of that and add in a morning session if you are able. But if you aren’t – no worries! It’s hard to find a time when you know your baby will nap well for you. It’s okay if this isn’t all figured out by 4 weeks. When things are more predictable, choose a time in your schedule when you can be consistent and faithful (morning, afternoon, or night, truly)! That consistency is so important for stimulating the supply and demand system.

When you are done building your stash, you can slowly “wean” that session(s) away by decreasing the minutes of time you pump each day or two. A gradual slow down of “demand” should help mitigate any engorgement or uncomfortable excess supply. I’ve got so much more for you here on weaning, too.

The takeaway on building a breastmilk freezer stash

Ultimately, you want to remember that all of these choices are extremely individual to you and your life. What works for your neighbor may not be what you need – and that’s okay. There are many who do not fill a freezer full of breastmilk and are still more than able to exclusively breastfeed their littles for the first year of life. And there are many who love the peace of mind that full freezer gives them.

You can land wherever you need to on this topic. There is no right or wrong answer here, as long as you are honoring YOUR needs and YOUR relationship with your little. The rest will fall into place.

For even more on this topic (and my personal thoughts), check this out over on my Instagram.

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About the Author

Lo Mansfield MSN, RNC-OB, is a specialty-certified registered nurse in obstetrics, postpartum, and fetal monitoring who is passionate about families understanding their integral role in their own stories. She is the owner of The Labor Mama and creator of the The Labor Mama online courses. She is also a mama of three, a University of Washington graduate (Go Dawgs), and is currently an expat in Haarlem, Netherlands. 


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