How Do I Know What Size Flange Insert I Need? Willow's Flange Insert Sizing Guide

Amidst the multitude of baby essentials, one unsung hero quietly takes its place – the breast pump flange insert. It might sound like a minor player, but many pumping moms will tell you it's your secret weapon for pumping success and a game-changer when the flanges with your pump simply aren’t cutting it.

This article isn't just a guide – it's your trusty sidekick, ready to decode the potential signs that your current flange might be missing the mark.

You're in the midst of your pumping routine, and something just doesn't feel right - but you’re not sure what the issue is. Chances are it’s your flange. Not all flanges are created equal, and recognizing when your flange isn't up to the task is the first step to a more comfortable and successful pumping experience.

 Here are a few signs that your flange is the wrong size: 

• Pinching: The right size flange should be a perfect match for your nipple – no friction, no pinching, and definitely no excessive pressure or pain. If you are feeling pain when pumping, that’s a red flag and likely a signal that it's time to reevaluate your flange fit.

• Rubbing: Some soreness is completely normal when you’re adjusting to your pump. But if you’re experiencing persistent discomfort or your nipple is rubbing against the side of the flange, it’s a sign that you may need a different fit.  

• Lack of suction: While we don’t want you to experience pain or pinching during your breast pumping session, we also want to make sure you are getting enough suction to maximize your milk output. If you don’t feel gentle suction on your breast while using your Willow pump, there’s a good chance your flange size is too big and it’s time for a smaller size.

• Decreased milk output: Using the wrong size flange can impact stimulation, which can also affect the rush of oxytocin that triggers letdown and milk production. If you notice a decrease in milk output, there’s a chance your flange is too large and that can result in insufficient emptying of your breast.

The Willow® Sizing Insert Set is your secret weapon for a successful pumping experience that's all about you. Designed for moms who measure smaller than 21mm, these inserts are like a personalized fit session for your comfort and output optimization.

Based on years of sizing data (more than 350,000 women have pumped with Willow!), we know that most moms find the best fit using a 17mm or 19mm insert, and rarely need a size larger than 24mm, but some also need smaller. That’s where the Willow sizing inserts come in.

We've got you covered with pump sizing inserts in 13mm, 15mm, 17mm, 19mm, and 21mm. They are the ultimate, customizable solution for getting your right flange size when paired with 24mm Willow flanges and containers.

Now that you've figured out some of those subtle signals that the flange fit is off, it’s time to learn how to select the perfect insert to elevate your pumping game. We recommend that you measure your nipple size frequently, especially if you experience any discomfort or changes in breast milk output.

We’ve all struggled to match our measurements to a size chart, and that’s an additional stress you don’t need when trying to find the correct size accessories for your breast pump. That’s why our carefully designed nipple measuring tool is your ticket to nailing down an accurate measurement of your nipple size. 

Just follow the instructions carefully and don’t forget: you should measure one hour before or after breastfeeding or pumping for the best results. You will also want to measure each nipple individually since your nipples are sisters, not twins. You might even need a different flange and flange insert combination for each side to get the perfect fit!

Once armed with your measurements, take a look at the comprehensive table in the tool. It neatly matches up your specific measurements with the ideal insert size. Like any personalized fit, expect a bit of trial and error as you figure out your perfect match. It’s completely normal for your nipple size to change throughout your pumping journey, and you may even need to switch to a different size flange or insert at some point. If you experience discomfort or decreased milk output, that’s your sign to measure your nipples again.

For all you moms out there uncertain about sizing, don't hesitate to reach out to Willow's customer support—we’re just a message away. The Willow Perfect Fit Bundle was also designed to help you find your perfect fit (plus it provides access to one of our sizing specialists!). 

Let's talk about making the most of Willow sizing inserts to up your comfort and get that perfect fit, especially if you're rocking a range size equal to or smaller than 21mm. These inserts are your go-to companions for the Willow breast pump, and they play nice with 24mm flanges and containers. No compatibility issues here!

Before you dive into using your sizing inserts for the first time, there are a few easy steps you’ll need to take to make sure that your inserts fit just right and are ready for use with your Willow Pump:

• Double-check your insert size using our step-by-step sizing guide.

• Give those inserts a good five-minute boil and let them air dry.

Quick note – Your sizing inserts are non-sterile when they first arrive at your door, so a little boiling action is necessary to make sure they are ready for your first pumping session.

Now that your sizing inserts fit perfectly and are sterilized for safe use, it’s time to get them assembled with your Willow Pump! Here’s what you need to do:

• Pop each insert into the 24mm flange or container tunnel. 

• Push the sizing insert in snugly until the edges are flush. 

• When your pumping session is finished, grab one side, give it a twist, and pull.And here’s a pro tip to make the transition smoother for your nipples – think about using nipple balm or pumping spray during the adjustment period.

It’s important that you wash your sizing inserts after each pumping session to prevent the growth of mold and bacteria. You’ll want to make sure you wash your hands with soap and water before you start cleaning your inserts. We also recommend dedicating a wash basin solely to the noble task of cleaning pump parts and baby-feeding gear. After each use:

• Remove the insert from your Willow pump and give it a good rinse.

• Let it soak in hot, soapy water for about five minutes, followed by a solid one-minute wash. Rinse off thoroughly.

• If you spot any stubborn residue, repeat the process.

• Let it air dry, and find it a dry spot for optimal storage.

There you have it – easy steps for a smooth ride with your Willow sizing inserts.

As a mom, you're navigating a path filled with both joys and challenges. With tools like Willow's Nipple Size Guide, we aim to make the pumping experience a smoother ride. We also have the Willow Perfect Fit Bundle to help you find your perfect fit, featuring an exclusive 1:1 virtual visit with one of Willow’s sizing specialists. Plus, with Willow’s sizing inserts, we’ve made it easy for every breastfeeding mom to get a custom fit for successful pumping sessions.

Trust your instincts, pay attention to the subtle signals your body gives you, and, most importantly, don't be afraid to seek support. Happy pumping, moms! Your journey is uniquely yours, and Willow is here to ensure it's as comfortable and rewarding as possible.