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Open or Closed Pump System: Does it Matter?

Pump system on a table near a chair.

Some people think that it doesn’t matter if a breast pump system is open or closed. I disagree. I once saw a demonstration where the milk was pulled back into the motor.

Sorry, but the “ick” factor was just too much for me.

But let me get my emotional baggage out of the way and instead describe how the pump systems differ in terms of what these terms mean, why the barrier matters, and why a presumed “work-around” doesn’t actually work.  

What does it mean?

To my knowledge, all electric pumps are operated with a motor as part of the mechanism.  

Whether the pump system is an open system or a closed system depends on one factor: A barrier.

A closed system pump has a barrier between the collection kit and the actual mechanism of the pump.

An open-system pump, however, does not have such a barrier.

Why the barrier matters

The barrier prevents contamination of the milk; the milk cannot get into the actual pump mechanism. Common contaminants are bacteria, viruses, and fungi (specifically, mold.)

So the bigger question is, does it matter if the contaminated milk is consumed by the baby?

Well, you tell me!

To my knowledge, we have no studies to prove that such contamination is harmful. (And who would fund those studies?)

But my question is, “Why wouldn’t it be?” Do any of us want to expose ourselves or anyone else to contaminated food or fluid?

You’ve heard me say that milk collection and storage “depends” on so many factors. So, here I’ll say that if I had a preterm or compromised infant, I would immediately be cognizant of how the pump is part of the collection process.

Can you work around the threat?

People often ask if they can simply “sterilize” the inside of an open pump system or buy new parts or something.

The answer is, no.

First, there’s a big difference among these five activities:

  • cleaning
  • disinfecting
  • decontaminating
  • sanitizing
  • sterilizing

Hence, I cringe when I read the suggestion to “sterilize” the pump’s mechanism. I don’t think that’s possible.  To do any of the above-mentioned five activities:

First, you’d need to completely disassemble the pump’s innards. Most of us don’t have the skill do that, much less to put the parts back together so the pump works!

Second, I don’t see how you would actually perform one of those activities on some of those parts. Have you seen those parts? (View here; view the motor, gear box, wires, etc., start around 1:10.) To me, that just doesn’t seem realistic.

These are by no means all the pumps on the market. But they represent what I would consider to be fairly popular models that offer closed pump systems.

                                       Closed System Pumps

Ameda                           Elite™, Platinum™, portable MYA

Ardo                               Calypso, Carum

Freemie                          Liberty II, Independence

Lansinoh                        Signature Pro™, Smartpump 2.0

Medela                           Symphony

Avoiding misconceptions

A multi-user pump may or may not have a closed pump system. Stay tuned for a post on multi-user versus single user pumps!

I can’t tell you what to buy. I could probably talk all day about criteria for buying one breast pump over another. But certainly, whether the pump had a closed system would be a major selling point for me.

How did you choose your pump? Is it an open or closed pump system? Share your experiences in the comments below!

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  1. Kim Cook

    I did not know there was an open system on a pump! And my other assumption is that our multi-use pumps are close systems. Interested to hear your comments

  2. Marie Biancuzzo

    Kim, always great to hear from you! This whole open-versus-closed-systems topic is something that doesn’t get much discussion. Stay tuned, I have an entire post scheduled to talk about multi-user pumps versus single-user.

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