Foamy Breast Milk: 3 Causes and How to Prevent or Remove Bubbles

Whether you’re leaving your baby for a period of time or your baby just can’t seem to latch on, pumping is a necessary evil. It’s pretty cool to be able to see the milk your body is producing for your little one. But what if when you pump you end up with foamy breast milk in the bottle? Did you just waste your precious time and milk!?

Quick answer: it’s not wasted, so breathe easy. But you will need to figure out why you have foam in your breast milk after pumping and take steps to prevent it. We’ll discuss all of that in this article.

With both of my children, I had the unfortunate experience of not supplying enough breast milk. I ended up pumping after every latched feeding to increase my milk supply as much as possible and get every last bit out so I could provide as much breast milk to my babies as I could.

During my experiences with breast pumping, I encountered it all: incorrectly sized flanges, spilled milk (the AGONY), and foam in my breast milk. After some trial and error (and false assumptions), I figured out what was causing the pumped breast milk to look foamy. After that, I was able to make sure it didn’t happen anymore.

Why is my breast milk foamy?

Breast milk foam can be caused by a number of factors (and you may even have more than one of these contributing to your frothy breast milk).

Once you can determine what’s causing the bubbly breast milk, you can take steps to prevent it or remove the bubbles.

Is it normal for breast milk to be foamy?

While bubbles in breast milk are fairly common (and therefore a normal occurrence), they are not something you actually want to be in your breast milk. This is because of the negative effects the extra air can have on your baby.

For this reason, you’ll want to make sure you take the steps below to prevent and remove air bubbles in your breast milk.

But first, let’s discuss why your breast milk is bubbly when pumping.

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Causes of Foamy Breast Milk

There are three common causes of bubbles or foam appearing in breast milk, which we’ll discuss in detail.

Problem with Breast Pump Connections

Foamy breast milk while pumping is often caused by the act of pumping itself and does not mean anything is “wrong” with your breast milk.

There are two points of connection in your breast pump that, if not correctly attached, can lead to breast milk foam.

The first is the membrane present in many breast pumps (including automatic Medela pumps like the one I used). If it’s worn out or not completely snapped into place, it won’t close properly during the suction action and can allow air to mix with your pumped milk.

Secondly, you’ll want to make sure the flange of your pump is fully pressed against your breast. If any air is able to move around your breast and into the suction tube while pumping, that air will be sucked in next to your breast milk and cause it to become extremely frothy.

You may even be able to see bubbles in the flange while pumping, even if they aren’t immediately noticeable in the bottle.

Manual vs. Automatic Pumps

Some women starting out with hand pumps (like the very affordable Haakaa) incorrectly assume it is the manual breast pump making the milk foam, but this is not true. I only used an automatic pump and I still ended up with bubbly breast milk sometimes.

The truth is, when hand-pumping, you are more likely to accidentally pull the flange away from your breast instead of keeping it pressed firmly against it. This action of pulling away introduces more air into your breast milk as it’s pumped.

Both automatic and manual breast pumps can achieve excellent results with bubble-free breast milk. It just takes practice!

Forceful Letdown

If your breasts are extremely full and/or you have a very quick letdown, your pump may draw a large amount of milk when you first start pumping. This “spray” into the bottle can cause bubbles to form that may not go away quickly.

There is a way to help prevent bubbles in breast milk caused by a strong flow, and we’ll discuss that in prevention methods later.

High Lipase Presence

Milk is naturally bubbly when shaken, whether we’re talking about breast milk or cow’s milk. This is due to the protein content, or lipase, present. The more lipase your breast milk has, the bubblier it may appear as your pumped bottle fills up (especially when combined with a forceful letdown).

Is high lipase milk bad for baby?

There is zero evidence that breast milk with a high lipase content is bad for your baby to drink. If your milk doesn’t normally have a high amount of lipase, however, it may have a different taste (or a more sour or soapy one in the case of pumped milk). These changes may make your baby not want to drink it.

As for the bubbles, we’ll talk about how to reduce those below.

How do you prevent high lipase in breast milk?

Unfortunately, there’s not really anything you can do to prevent your body from creating breast milk with a high lipase content. But you can treat your breast milk before refrigerating or freezing to remove the high lipase content and keep it from changing flavor too quickly.

This article at Exclusive Pumping is a great resource for learning how to scald your milk to remove the lipase.

Soap Bubbles in Breast Milk?

It is highly unlikely that any bubbles appearing in your pumped bottles are caused by soap residue left from cleaning, so don’t be too quick to throw it out!

As explained above, even if your breast milk tastes soapy, it is probably just a result of high lipase content. Or, if you’re double-pumping and only one bottle has bubbles, that side probably just didn’t have an airtight connection to your breast.

How Breast Milk Foam Affects Your Baby

What happens if your baby drinks an untreated bubbly bottle? Unfortunately, nothing good.

Spit-Up

The extra air in fizzy breast milk can cause your baby to spit up more than normal. Their small tummies can’t hold all of the liquid and air in there together, and when bubbles come back up, they usually bring some milk with them.

Keep in mind, though, that it is also possible to overfeed a baby. You want to be careful not to keep offering a bottle to a baby that has eaten enough. (I know, it’s hard to toss that precious breast milk!)

Gas, Colic, and Tummy Pain

If the air in the bubbles doesn’t come back up, it will go on through their digestive systems. This can cause stomach pain, gas, and general unhappiness (colic).

Since it’s difficult to completely remove ALL air bubbles from a pumped bottle, I strongly recommend using bottles designed to reduce colic and reflux.

What about foamy breast milk poop?

Foamy baby poop is not caused by bubbles or foam in the milk your baby is drinking, because they would have turned into gas by the time the stool was formed.

Frothy stools are actually a sign of your baby not getting enough hindmilk (or too much foremilk), so make sure you’re pumping long enough to get to the nutrient-rich hindmilk for each feeding.

How to Prevent Foamy Breast Milk

Now that you know leaving bubbles in your baby’s bottle is not a good idea, let’s discuss how to prevent and get rid of them.

Hand Express Before Pumping

If your breasts are really full or you have a history of forceful letdown (a lot of milk coming out quickly at the beginning), expressing some breast milk with your hand prior to pumping can help prevent that force from creating bubbles.

You can hand-express into a separate bottle if you don’t want to waste it, or straight into the sink. Just don’t express too much before each pumping session or you may end up with an oversupply of breastmilk.

Let the Breast Milk Sit Before Feeding or Refrigerating

Foamy bottled breast milk will often lose bubbles on its own if it is given time to do so. Instead of immediately feeding your baby with (or refrigerating) breast milk that has been pumped into bottles, allow it to sit on the counter at room temperature for up to ten minutes. You may even see the bubbles “popping” during this time.

Add Gas Drops to Breast Milk

If your refrigerated breast milk has bubbles that still haven’t gone away after it’s warmed for feeding, there is a way to help remove the remaining bubbles. Just add some gas drops directly to the breast milk!

Believe it or not, adding simethicone drops to your breast milk can make a huge difference in the number of air bubbles present. You may see them disappear almost instantly. Just gently swirl the bottle after adding the drops to mix them in; shaking will have the opposite effect that you want!

And don’t worry: it’s perfectly safe to give an appropriate dosage of gas drops to your baby at every single feeding, so even if you need to add it to every bottle of breastmilk, it won’t cause any harm.

Store Breast Milk in Special Bags

You probably already know this, but using bags specifically designed for storing breast milk is the easiest way to get the bubbles out of your milk.

After pouring your pumped milk into the bag, just squeeze out any air bubbles that occurred in the process before sealing.

Air Bubbles in Breast Milk Bag

If you don’t squeeze out every pocket of air in your breast milk bag before freezing, the flavor of the milk may change by the time it’s fully frozen. This can lead your baby to reject it after it’s thawed.

Air in the bag can also cause freezer burn to happen quickly, ruining your milk. (Remember, though, that breast milk stored in the freezer for more than a few months can develop freezer burn either way.)

How do I know if my pumped milk is bad?

There are several tests you can use to determine if your breast milk is actually bad, such as:

• The smell test (is it sour?)
• The swirl test (does the fat not mix back in when swirled?)
• Has it been in the refrigerator (NOT the freezer) longer than four days?
• Was it stored improperly?
• Does it taste bad to you?

This article goes into detail on each of these tests and how to make a determination based on your findings.

Why does my breast milk look watery when I pump?

If your breast milk looks clear or watery when you start pumping, that’s okay and totally normal. This is because your letdown begins with your foremilk which is designed to quench your baby’s thirst.

After a while, you should reach your hindmilk, which contains most of the fat and nutrients your baby needs to grow.

If your milk never appears to get “thicker” during pumping and you don’t see a separation of the fat at the top of the bottle after refrigerating, it’s likely you’re not pumping long enough to get to the hindmilk. Adjust your pumping time to make the most of your breast milk.

Breast Milk Color Chart

In addition to worrying about foamy breast milk, you may have concerns over the color of your breast milk (which seems to always be changing!). This chart should help ease your concerns.

I hope you’ve gained some valuable insight and won’t be too quick to dispose of foamy breast milk in the future!

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