How To Select The Correct Size Medela Breastshield

by poshm2 on October 14, 2011

The Medela PersonalFit Breastshield.

We have put together some information to help Mums decide how to select the correct size Medela breastshield for their needs - Introducing the Medela PersonalFit Breastshield.

It’s a fact that we are not all the same size in the Nipple department – at last this has been addresses by Medela with the special PersonalFit breastshields.

Medela have very thoughtfully developed a range of special breastshields called ‘PersonalFit Breastshields‘ – this aptly named product was created to accommodate various nipple sizes and in so doing, alleviate the associated problems with soreness and pain that some mums experience.  It is fair to say that most Mum’s get along  just fine when expressing using Medela’s standard breastshields. The regular or standard breastshield has a tunnel width of 24mm. However, as the nipple expands whilst expressing due to the suction produced it can soon become apparent that ‘standard’ just isn’t right for you. Many women find that within several sessions with their machine, they are struggling with poor yield and may even experience soreness of the nipples due to chaffing. This problem is caused by the ‘tunnel width’ of ones breastshield being too small. With continued use an undersized tunnel width may become so bad as to cause real soreness and a blister like effect. It is important to spot this problem before it causes any setbacks which could result in not being able to express for some days whilst the nipples and areola recover. The is also the problem of using a breastshield that is too large and which will allow the pump to pull in more nipple and areola than is necessary for efficient expressing. This can again cause soreness and discomfort in use. In these cases, it is possible to move down in size.

Medela breastshield standard fitting 24mm

Medela have produced a special range of ‘PersonalFit’ breastshields to address to problem associated with varying nipple size and expressing with an electric breast pump. For smaller than average nipple size, Medela have a 21mm option and for larger than average nipple sizes, Medela have 27, 30 and 36mm options.

Take a look at the diagram below to get an idea of the sizes available. The image is not exactly to scale to in reality any variance my be more or less apparent.

Size options for the Medela PersonalFit breastshield

Finally, I can report that these special PersonalFit breastshields are hose connected to your breast pump and as such are compatible with all Medela Breast Pump models. It is even possible to use these with a Mini-Electric single as the motor unit can connect directly onto the back portion the same as with the standard version. Basically, nipple soreness and pain – problem solved. The above images are copyright of

For trouble free expressing, your nipple(s) should be able to smoothly and easily glide back and fro in the rhythmic action produced by your breast pump without restriction. See here a helpful illustration prepared by Medela

In the first image below, you can see that the nipple is too large for the breastshields internal tunnel width, it is hardly able to enter into the tunnel area. In these cases, one will need to investigate using a ‘shield one or even two sizes larger.

breastshield too small

In the image below, you can see that there is a lot of room around the nipple. In these cases, the breast pump would likely attempt to draw in a lot of the surrounding areola at the base of the nipple. A smaller breastshields is required here.

breastshield too large

Let me know if the information here was interesting and helped you with your efforts to decide upon the correct fitting Medela PersonalFit breastshield for your needs. Go ahead, leave a comment below :-)

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