How do I know which flange size to use?

How do I know which flange size to use?

Did you know that only about 40% of us are using the correct flange size?! Unfortunately, most breast pumps come with a standard issue 24 mm flange, when most us require something much smaller. A properly fitted flange is essential to collect the most milk and most importantly, makes pumping WAY more comfortable! 


Thankfully, most lactation consultants offer flange fittings to determine which size is the best fit for your unique anatomy. We suggest meeting with an LC to be measured towards the end of your pregnancy, so that way you’ll already have established a relationship with a provider should you require additional support after birth. The last thing you’ll want to be doing is frantically Googling IBCLCs at 3 am with a crying newborn and cracked nipples, so do yourself a favor and have one at the ready before babe makes their debut. 


That being said, it is also possible to do a flange fitting at home with everyday household items. All you’ll need to do is grab a few coins and batteries to measure your pre-pumped nipple size. Start with the smallest item, the AAA battery and compare it to your nipple’s diameter. If it’s too small, move up to the AA battery and see if that matches. If not, continue until you find the most similar sized item and match it to the corresponding flange size listed below. 


AAA Battery = 11 mm

AA Battery = 15 mm

Dime = 18 mm⁣

Penny = 20 mm⁣

Nickel = 22 mm⁣

Quarter = 24 mm⁣

Dollar = 26 mm⁣


Then, add 1-3 mm to that number to determine your approximate flange size. 


A few things to keep to mind: this method is not as accurate as actual fitting done by a professional, but it is a good place to start. Further, be sure to measure your nipple ONLY - this measurement is not based on your breast or areola size. This can be confusing, because when baby feeds directly from the breast, we want more than just the nipple in their mouth, whereas in this case, we’re just measuring the nipple.


Once you’ve got an idea of your correct flange size, “try it on” to see how it feels. Before pumping, you should have about a small amount of space around your nipple in the flange and no space around the areola. Turn the pump on. Your nipples should not rub against the sides of the flange tunnel, there should be no pain and your nipples should not be changing colors (ouch!). If you experience any of these concerns, this is probably not the right fit. 


You’ll also want to assess how well the pump moves your milk: you should not feel as though there is still milk in your breasts after a pump sesh, you should not be getting reoccurring plugs and you should not see a decrease in milk supply. Again, if you’re experiencing any of these issues, a change in flange size should help! 


Lastly, using a little lube can also help boost comfort! Many retailers sell special sprays to lubricate your flanges, but you can also use good old fashioned coconut oil (is there anything coconut oil can’t do?!). 


Happy pumping!

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