Parts of a Breast Pump: An Introductory Guide to Everything you Need to Know

By admin

If you are about to start breastfeeding and are planning in expressing you will need to research the best breast pump for you to ensure you get off to a great start.

Whatever breast pumps you are considering you will need to understand the different parts so that you can use them accurately. 

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You may feel overwhelmed when looking at different parts of the breast pump, especially when it comes to assembling it.

We take a look at each part of the great pump and what it is used for, to help you when the time comes to start expressing your milk

Breast Pump Parts

The main components of a modern electric breast pump are:

  • Breast pump 
  • Flanges (sometimes called shields)
  • Membranes
  • Valves
  • Tubes
  • Connectors
  • Milk collection bottles (or bags)
  • Backflow protectors (on some models of a breast pump)

Each part of a breast pump has a function, with some lasting the duration and others that will need replacing at certain points of your expressing journey.

You will also need to know which parts of the breast pump need sterilizing on a regular basis. 

Breast Pump

The breast pump ( or pumps if you have a double pump such as the Spectra Gold or the Medela) is the main component of the machine as it creates the suction needed to extract milk from the breast.

The vacuum in the pump works gently with your breast, first massaging and then sucking milk out of the breast and into the bottle attached.  

Manual Vs Electric Breast Pumps

When it comes to deciding on whether to buy a manual or an electric breast pump, you will want to consider the following pros and cons of each.

Manual breast pumps pros:

  • Has a lever that you can squeeze at your own pace and intensity
  • You can control how much milk is expressed more easily
  • They are small and light so easy to carry around in your bag
  • They do not require any batteries or power supplies

Manual breast pumps cons:

  • Not as quick at expressing milk as electric pumps
  • Not as effective for some women
  • It can become tiring 
  • You cannot easily multi-task when pumping 

Electric breast pump pros

  • Allows you to express quickly 
  • Adjustable speeds
  • Can be recharged if you choose a brand with a battery pack

Electric breast pump cons

  • Heavier than manual breast pumps so not as easily transportable 
  • Can take time to adjust to 
  • While the vacuum on the electric pump is gentle it may be too fast for some women
  • Allows for hands-free pumping for your convenience 
  • Can help with milk blockages or breasts that do not produce milk easily when pumping 

Breast Pump Flanges and Shields 

The plastic cone-shaped shield of the breast pump is called the flange which fits around your vest. Your nipple will be pulled into the funnel part of the flange as the vacuum starts up.

If you don’t like the sound of a plastic shield you can look at brands that use a softer silicone shield. 

It is vital that the shield and flange of the breast pump fit snuggly to your breast or pumping will be painful and you will not express milk as quickly as you would like.

You may also encounter sore and cracked nipples or blocked milk ducts. 

You measure the correct size by the diameter of the nipple. A local lactation consultant or pre-natal nurse may allow you to try different breast pumps and breast shields to see what size fits best. 

Membranes and Valves Duckbill Valves

The plastic valves on your breast pump connect to the flanges and allow milk to pass through them through the holes in them.

Each valve will contain flexible membranes that open and close the valve depending on the suction coming from the pump.

Duckbill Valves

A duckbill valve (named as it looks like a duck beak) is made from silicone rather than plastic and is slightly different than the standard valve.

As the beak opens and closed when the vacuum starts, the milk drips into the flange and out into the receptacle that collects the milk. 

When your breast pumps start to slow down or stop working the valves and the membranes will be the first things to check as they can become slack and will need replacing.

They are reasonably cheap to replace and parts can be found easily online. 


The clear plastic tubing on breast pumps is the main connector between the pump and the shield. The milk flows out from the shield into the bottle and is the main part of the pump that you need to worry about when it comes to cleaning.

The tubes obviously become very wet so are prone to mold if you do not clean and dry properly. One tip to keep the tubes dry on your breast pump is to keep the machine running even after you have finished expressing. This will help dry out the tube.

When the tuning starts to turn brown it may not necessarily mean that it is harmful to your baby but you may want to air on the side of caution and replace the tubes. 

Collection Bottles

The collection bottles will be attached to the flange or a connector, depending on the type of breast pump you buy.

Different breast pumps also have different size openings so you must make sure you buy the correct bottle size, although most breast pumps come with a couple of bottles.

Some breast pump brands come with collection bottles that your baby can drink out of which makes it a convenient choice. 


Some great pumps, such as the Medela and the Spectra Gold, have connectors that connect the shield at one end and the collection bottles at the other.

The addition of the connector is for hygiene reasons as they can easily be taken off to clean.

Another reason to buy a pump with a connector is that you can try a different type or size of the shield if one does not feel comfortable or stops working for you.

It is common to adjust the size of the shield as you reduce the amount of feeding when your baby starts to wean and your breasts reduce in size.

Connectors on the Spectra on the breast pump are known as a backflow protector which, again, prevent mold from growing on the pump in the hard-to-reach crevices. 

Sterilizing Breast Pump Parts

You need to ensure that your breast pump is kept clean and mold-free at all times.

This means that the below parts of the pump needs to be sterilized on a regular basis:

Tubing on breast pumps can become easily discolored if they are boiled rather than sterilized and some brands recommend a certain way of cleaning them so do check the instructions.

If your tubing does become discolored or you are worried about it not being clean you can buy replacement tubing which is not too expensive.

Aside from the tubes, other parts listed above can be boiled as well as using a store-bought sterilizing solution. 

Other parts of your breast pump that can be replaced include:

  • Valves (when they wear down and become slack so should be changed every 3-4 weeks)
  • Membranes (should be replaced at least every 4 weeks)
  • Connectors

Replacement Parts Insurance Cover

If you receive a breast pump via your insurance cover you may be entitled to claim for replacement parts. You should check out the terms and conditions of your insurance before deciding on a breast pump so that you know what the costs of replacements are likely to be.

If you know that your insurance will not cover the cost of replacement parts then you should do some research ahead of buying a breast pump.

You may have a rough idea of how long you want to breastfeed and express milk so this will give you an idea about how many replacement valves and membranes you will require throughout your breastfeeding journey.

Some replacement parts are more expensive than others and, if you get an older style breast pump, you may struggle to find replacement parts easily.

You can also speak to friends and family for advice on how they were supported by their insurer. 

Whatever type of breast pump you buy it is important to familiarize yourself with all of the parts so that you know how to use the pump correctly.

This is something that you can do before you have your baby as it will allow you the time to become familiar with your pump.

Understanding what each breast pump part is and how to look after it will also reduce the amount of pain that you experience when expressing milk in the early days.

It will also ensure that you clean your breast pump fully so that you keep yourself and your baby safe.