Flange Fit - One Size Doesn’t Fit All

Let’s talk about flange fit!

A flange is the part of a pump that the breast/nipple goes into. They can sometimes be called different names such as breast shield, tunnel, or funnel. They often come as a size 24mm as the standard diameter, but flanges aren’t “one size fits all”. If you think about how everyone has different shoe sizes, then it makes sense that everyone would have different nipple sizes too. If you are wearing the wrong shoe size, it can be uncomfortable and not feel right. Same thing applies to your pump flange size.

The size you use can be super important for your comfort level and the amount of milk you can pump out. If you are finding that you have pain, even on the lowest suction setting, this could be because the size is not quite right.

If the flange you are using is too big, it can pull in too much areola and cause friction, pain or wounds. You won’t be getting the stimulation you need and so this can decrease the amount of milk you can pump.

If the flange is too small, it can also cause pain, skin trauma, and reduce the milk flow because it will be compressing the nipple.

So what do you do if you are worried you are using the wrong size?

There are a couple of things I would suggest. First would be to reach out for support from a lactation consultant who is experienced in this area. They will be able to guide you through it and measure you correctly and check that it really is the fit that’s causing you issues and not other factors such as an insufficient pump motor.

If you are unable to seek the help of a LC, then there are some printable measuring guides online that you can print and cut out. Just make sure that you use the “true to size” setting on your printer. Alternatively, diameter rulers are inexpensive to purchase from stationary shops.

What do I measure?

It’s important to understand the anatomy of your breasts. There are a couple of things to keep in mind to find your correct size. First, when you are measuring your nipple, make sure to measure the base of your nipple, where the nipple meets the areola. Second, make sure you are not measuring directly after you pump or have just breastfed. The size of your nipple is the size flange I would suggest starting with.

I’ve measured, now how do I get the right flange size for my pump?

This is going to depend on the brand of pump you are using. Some of them you can just order new flanges in the correct size, others are going to require a small silicone insert that slots into the plastic flange tunnel. Check out your brand of pump for other sizing options as your first port of call. The newer brand pumps on the market are catching on and often will give you more sizing options in the package or the option to purchase the little silicone flange inserts. I recommend first pumping with the size your nipple measures, then trying one size up and one size down from that.

If you are an exclusive pumper or are expressing later on in your feeding journey, you may find that your size needs to increase slightly. This is because nipples are made of elastic muscle fibres and can increase with pumping or latching suction over time.

How do I know I’ve got the right size?

 When you pump it should feel like a gentle tug or nothing at all. You should start to see milk within the first 30 seconds and it should be spraying from the nipple. the majority of people I see usually need a 19mm/17mm/15mm.

Sometimes it can be helpful to lubricate the nipple with a bit of coconut oil or olive oil.

Unfortunately even sizes don’t exist yet so it will be a bit of trial and error if you are measuring 16mm/18mm etc.

If in doubt, send me a message and we will figure it out together. Over the past year, I would have supported over 500 people with lactation and I could count on one hand the amount that would have needed a 24mm or above. Here’s hoping that as the technology grows, the manufacturer knowledge does too.