6 Reasons Your Breast Pump is Losing Suction



As pumping moms, we get accustomed to pumping a certain amount of breast milk at specific times of the day. 

6 ounces in the morning or 4 ounces after lunch, etc, etc. 

Have you ever started a trend of pump less than you know you should? Have you ever thought, “why is my pump losing suction?”

It’s not your imagination. There are reasons that your pump will lose suction which will inevitably affect your output of breast milk.

The good news is that most of these reasons are quick fixes. Breast pumps are like any other device in our life and require a certain amount of maintenance to remain at their peak performance.

6 Reasons Your Breast Pump is Losing Suction


Here are 6 reasons your breast pump is losing suction and how to fix it!

1 – The Batteries Need Replacing

If you are using a portable pump that takes batteries, then that is the first thing that needs to be checked.

As the battery power gets low, the pump will start to lose suction. It doesn’t take much for the pump to start to underperform when running on batteries.

The Medela Pump in Style, for example, has the optional battery pack to make it portable.

I found that if those batteries were below 50%, the pump started losing suction.


Medela Pump in Style Battery Pack

In pumps that have a rechargeable built-in battery like the Medela Freestyle and the Spectra S1, it is best to ensure their battery does not get too low.

Both of those pumps are powerful but have a noticeable difference in suction strength if the battery gets low. Make sure you are recharging the battery often as needed.

(Related: Have a Spectra S2 and want a battery pack? Check out what your options are!)

2 – Replace the Membranes


Membrane and Valve

There are a few pump parts that you will need to replace periodically to keep your pump performing at it’s best.

The membranes are the part that you will be replacing the most often.

Most pump brands have their own timeline on how long you can expect the parts to last. The membranes likely need to be changed out every 3 months.

If you are pumping multiple times per day, you might need to replace them every 2 months.

The membrane is the small, flexible part that fits the valve.

The reason this small part is so vital to your pump strength is that it is what moves back and forth creating a seal as the pump works.

If you have a worn out membrane, then the seal will not be as strong and thus the pump suction will lessen over time.

The Medela membrane is a small white piece that is separate from the valve.

You would not need to replace the valve on the Medela pumps unless it was damaged or became loose.


Medela and Ameda Membrane and Valves

Other pumps like the Spectra and Ameda, have the valve and membrane as one piece. They are typically just called

 valves. You would replace that entire piece.

Click here to see where you can buy replacement parts for your pump!

3 – Misfitting Breast Shield / Flanges

The pump part that fits your breast is called a breast shield or flange. They come in different sizes.

Typically small, medium, large, etc. The sizing is not based on the fanned part that fits over the breast but rather the opening for your nipple.


Your nipple should fit comfortably into the flange.

If there is too much space between your nipple and the flange, it can cause the pump to not suction correctly and affect your output.

A too small flange can cause pain while you pump as it smooshes the heck out of your poor nipple. Not the best set up for productive pumping.

This guide by Medela shows a good illustration of what a proper fitting flange should look like.

A lactation consultant can also assist in fitting you for the proper size.

If you are having pain when pumping or your output in extremely low, I would definitely check you have the correct size flange!

(Related: Click here to get the Basics on Pumping!)

4 – Tubing is Plugged in All the Way

This will likely be one of the first things you start messing with if you notice your pump losing suction.

The tube is the piece that connects the flanges to the pump and is where all the strength comes from.

Some of the pump brands, you really need to jam that tubing into the flange or the pump itself to get the connection just right.

When you notice a loss of suction, double check you have the tubing in correct place with a tight fit. Also, check for any defects or issues with the seal.



Check the tubing in pushed all the way into the pump and the flanges

The tubing is not something you should need to replace often especially in closed system pumps.

Open system pumps like the Medela pumps, will need it replaced periodically due to the build-up of milk that can happen in the tubing.

Cleaning and sanitizing the tubing is something that needs to be regularly done with open system pumps but closed system pumps you do not need to clean the tubes.

Not sure if you pump is open or closed? Click here to find out the difference.

5 – Pump Both Sides at the Same Time

If you are used to double pumping (pumping both breasts at the same time), you may notice a difference in output when you only pump one breast.

Studies show (source) that double pumping stimulates more milk ejections (let downs) versus single pumping. Your output will be more when you double pump.

I recently saw this video on this topic made by Medela that does a good job of explaining this exact topic.

It is always best to double pump if you can.

You will notice a considerable difference in the amount you are able to pump.

So if you think you are getting less by single pumping, it may have nothing to do with your pump but everything to do with the effect double pumping can have on expressing milk.

(Related: Need a good electric pump? Read our Pump Reviews, here!)

6 – Check Pump Settings

Another quick fix would be to ensure you are using your pump’s settings correctly.

If you are using an electric pump, then you likely have the ability to control the suction and speed of the pump.

Most moms who are starting out, have no idea how to use these controls effectively.

The point is not to turn up the suction strength and pump the hell out of your nipples until they have nothing left to give. The suction and speed have the distinct purpose of mimicking your hungry baby.

You can help your body achieve multiple letdowns and maximize your milk output by simply knowing how to properly use your pump’s settings.

Here is how to do that (keep in mind, every mother’s body is different so your tolerance of speed and strength may differ so use what is comfortable. Pumping should NOT hurt):

  1. Hook up your pump and start pumping with the suction on the lower side (again, everyone is different so how low or high will depend on your comfort level) and the speed on the higher side. When you are feeding a hungry baby, they start out frantically sucking at a fast pace but the strength is shallow. So that is what you are mimicking.


    Set the Speed HIGH and the Suction LOW

  2. Once your milk starts to let down, turn the speed lower and the suction higher. This mimics the deep suction once your milk starts flowing and your baby is swallowing.


    Set the Speed LOW and the Suction HIGH

  3. When the flow starts to lessen again, turn the suction back down and the speed higher to encourage an additional let down.
  4. Repeat until the pump session is over. In a 15-20 minute pump session, you should achieve at least two milk ejections/let downs. You might even get to that magical third let down.

Not sure when your milk is letting down? Click here to read more about how to tell when it’s happening!

Having issues with your pump can be frustrating but thankfully there are ways that you can fix the issue and get back to pumping those ounces! 

Have questions? Or a comment? Drop me one below!

Up Next:

Get the Basics on Pumping: Your Complete Guide -READ NOW—->

Working and Pumping Tips and Info -READ NOW—->

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Need Pump Parts for your Spectra Pump? Find out where to buy them!







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  1. Mayur says:

    Hello Team,

    My wife is using the breast pump from the last 4 months but suddenly one day the milk starts accumulating in the upper part of the pump and not flowing into the Jar. The pressure has to-be released either by stopping the pump or removing the pump and than the milk flows down. It is very time consuming, we tried 2 different pumps and the same issue persists. Is the size of the breast is a problem ? or any other solution


    • Heather Grace says:

      Hello Mayur,
      What pump (or pumps) is your wife using?

      Mt first thought is that there could be two things going on. 1) Sometimes with larger breast, the angle of the flange (the piece that goes onto the breast) can be slightly upward. Leaning forward to allow the milk to flow into the collection bottle helps though it’s not always very comfortable. 2) The valve could need replacing but you did mention that she has tried two pumps and it’s still an issue. This has me leaning toward it being the fit and angle of the flange/breastshield.

      You should not have to stop the pump in order for the milk to flow. The valve should release between the suction of the pump while pumping. It very well could be the overall fit of the flange. If she cannot tell if the flange is fitting properly, seeing a lactation consultant might be the best bet to assess what is going on and be sure she is using the right size. I would start there.

  2. Tricia says:

    Thanks for this advice! I’ve noticed my pump losing suction quite a bit recently, but none of my parts appear to be damaged. I’m going to try replacing the membranes and tubing to see if that fixes the issue. Definitely cheaper than buying a new pump!


    • Heather Grace says:

      Definitely, start with the membranes! It always amazed me how much of a difference it made to put a fresh pair on. I hope that is the solution for you! But if you were pumping find before and it just started losing steam, I would bet that will solve it. Come back and let us know!

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