What is a flange?
A flange is the funnel shaped part of a breast pump that makes direct contact with the breast and nipple. The funnel portion should sit comfortably on each areola so it creates a seal. The suction from the pump applies pressure just behind the nipple and the flange draws your nipple into the tunnel to collect the milk.
Why does flange sizing matter?
Using the right size flange allows the pressure to be applied just behind the nipple so that milk is extracted efficiently. Using a flange with the incorrect size could result in
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Inefficient or incomplete milk removal
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Longer pump sessions
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Low/decreasing milk supply
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Clogged ducts
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Mastitis
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Skin breakdown and injured nipples
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Pain/discomfort
What size flange should I use?
Most pumps come with one or two standard sized flanges, usually 24-25mm and 27-28mm. However flanges are available in many many more sizes and most people will need to purchase another flange (or two) to find the perfect size.
For all pump systems except Willow, the ideal flange size is 2-3mm larger than your nipple diameter. For the Willow pump, you ideally want an exact fit or 1mm larger.
Measuring your nipple can be challenging. Most pump manufacturers will recommend using a printed nipple measuring device. However these papers are flimsy and difficult to use. We have designed a new nipple measuring tool that slows you to confidently determine your nipple size without the need for a printer, camera, or a personal assistant.
How often should I change my flange?
Flanges should be replaced at least every 6 months, or sooner if they have cracks or deformations. Other components should generally be replaced every 3 months.
You should also change your flanges if your nipple size changes! Each breast may require a different size and may change throughout your breastfeeding journey. Nipples tend to change size after delivery, so we recommend waiting until after you have the baby to measure your nipple size. If pumping ever becomes less efficient or more painful, check your nipple size to see if it has changed! Our Nipple Sizer is designed with over-engineered materials to last the entirety of your pumping experience — even a teething toddler can’t traumatized this thing (trust me!).
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