Flange Size Matters!

april newsletter 2024 flanges


jeanette april 2024 newsletter

Jeanette Mesite Frem MHS, IBCLC, CCE is an internationally recognized speaker on pumping, feeding gear, and especially, updated flange fitting. She is the co-investigator for a soon-to-be-released research study, the first ever done looking at flange sizing. It compares “standard” flange fitting recommendations with Jeanette’s Flange FITS™ Method, which uses a different way of measuring and assessing flange fit. In her private practice, Babies in Common in Northborough, Mass., Jeanette teaches prenatal breastfeeding and childbirth preparation classes and provides support to families with breast/chestfeeding, lactation, pumping, and bottle-feeding concerns. We spoke about how her flange-fitting method, which she teaches to perinatal professionals, has improved pumping for so many lactating parents.



Julie Brill, IBCLC, CCCE, CLD: I’m so happy we’re getting to chat about proper flange size, because sizing down has been a game changer for so many of the clients in my clinical practice. Parents pumping at work and exclusive pumpers are grateful to be able to get more milk in less time. But I think the most impacted are those who are pumping to increase milk production; we’re seeing being properly sized often gives them the boost they need to keep going. We’ve come so far from when my kids were babies in the 1990s and there was only the 24mm flange!


How did you get started sizing parents smaller? It really was thinking outside the box, when the general thought was to go up if pumping was uncomfortable or the nipple was swelling during pumping. I remember about seven years ago when you handed me flanges that were sized in the teens. I thought they looked like they’d fit a doll! What gave you the confidence to encourage parents to try them?


Jeanette: Thank you for asking me about this topic—this is such a passion project for me. Like you, I have seen it revolutionize the pumping experience for so many. It’s also so rewarding for perinatal professionals who are doing this with their clients. I, too, was pumping in the early 2000s with standard size flanges; I wasn’t working full-time, but still needed to pump many times a week in addition to when I was at work, in order to yield enough for bottles when I was at work. And pumping wasn’t comfortable.

I eventually owned a maternity and parenting center where we rented pumps and sold flanges. We had a client with low milk supply who came to our breastfeeding groups. She shared she was getting more milk using a smaller flange: a 21mm. (Medela made these and then stopped for many years.) A few others found the same results. Eventually, as I started working as an IBCLC, more and more smaller flanges started to come onto the market and I was hearing they were working for some; so I learned from clients and colleagues. And I tried new things and found more success!


Julie: What are you seeing for an average flange size? How often do parents need a different size for each breast? And why do you think pump companies are still just making such gigantic flanges?


Jeanette: Based on my practice and what many, many lactation professionals around the world are reporting, the most common sizes are 13-16. If a parent tells me someone sized them as a 19 or larger, I wonder if that’s true. I know it’s true for some, but most people are 17 or below. Yes, pumping people often need a different size flange for each side, and that size may change over time. So, try smaller sizes (1mm by 1mm at a time) if pumping becomes uncomfortable or they want to see if they can yield more milk.

Why are pump companies making such gigantic flanges? It’s the typical answer: “that’s what we’ve always done.” No one has been questioning it until recently. And I think they wonder how they’d recycle all those flanges they’ve already made AND how they would fit new flanges into boxes if they change what they are doing. I’ve given most pump companies feedback about this but so far, very few seem to really care.


Julie: Lactation is a field where our base of knowledge is rapidly changing and yet we continually see resistance to innovation and even new research. What kind of reception have you received in the lactation community?

Jeanette: Many lactation professionals are curious and excited to see how different flanges work. Some are resistant, and ask “where is the evidence for using smaller flanges?” What is sad but true is there’s no evidence for using standard size flanges, nor the reason WHY standard sizes are the standard sizes! There are still too many lactation/perinatal professionals who think they should measure the base of the nipple and add a certain number of mm and to size the flange. Flange fitting is like shoe fitting: we can measure, but you must walk in the shoe a bit to decide if it fits. The human body isn’t standardized.


Julie: Can you share with us about the research you’re doing on flange size?


Jeanette: There’s never been research before comparing standard sizes with smaller sizes. But it’s not just about a flange being smaller. Sometimes smaller flanges hurt more, so our instinct is to NOT go smaller, for fear of those hurting more. But flanges that are too small aren’t painful, they just yield no milk and a nipple doesn’t move in them. We want to see the nipple gliding along the sides of the tunnel AND amazing comfort AND milk spraying most of the time. Fortunately, a wonderful research professor, Lisa Anders, PhD, RN, IBCLC of University of North Carolina Greensboro, reached out in 2022. Together we’re about to release the results of the first-ever flange fitting study! We’re in the writing-it-up phase now, hoping it will be published by this summer.


Julie: In my practice, I’ve seen parents in properly sized flanges comfortably turn up the vacuum on their pumps and get more milk in less time. Many say they no longer bother with hands-on pumping techniques, or there is less need for them. Do you think massage and compression is still necessary when the flanges are right?


Jeanette: I also see hands-on pumping isn’t always needed. I do like to recommend breast gymnastics/the milkshake before pumping, mid-pump, and toward the end. This gets the milk flowing, gets oxytocin flowing, and helps especially when the milk flow has stopped. That works well for many. Do all need it? No. Do some people still need massage and compression with pumping? Yes, because there are cases where flange fitting is more complicated. Some people DO need larger flanges because of their breast anatomy (we can’t see what is under the skin—we need to TRY different flanges to see what the best results are for comfort, milk sprays, and pumping efficiency).


Julie: Can flange fitting be done virtually?


Jeanette: Yes, but the gold standard is to have people measure their nipple TIPS (it’s NOT the base that matters) after they stimulate the nipple well. We need to know the diameter of the tips first. Then I’d recommend they purchase flanges that are that size and 1mm smaller and another one or two that are slightly larger. We need to have them TRY those flanges during one pumping session, as we work with them virtually, to assess comfort and sprays.


Julie: How can doulas and CLEs learn more about your sizing techniques?


Jeanette: I offer a course for perinatal professionals, which includes doulas, CLEs, and anyone else who works with parents who pump. The course also covers bottle feeding and other feeding gear, like nipple shields. It includes 5.5 CERPs and CAPPA CEUs. While there are aspects of lactation support that are in the scope of IBCLCs, I think knowing updated techniques and information about pumping and flange fitting and bottle feeding are things anyone working with perinatal families should know. More information about my course can be found on my website: https://www.babiesincommon.com/forprofessionals


Julie: Finally, what would you say to people concerned about the cost involved with trying different flanges?


Jeanette: Honestly, formula is expensive. Breastmilk isn’t free, we know it costs time. But we’re trying to help babies get more human milk and help people meet their goals for making milk. That may cost some money. Fortunately, flanges aren’t always super expensive.

I’d rather all perinatal professionals have flange fitting kits so they can do in-person flange fittings. Then people only need to purchase the ones that work the best. I’d love there to eventually be a resource for low-income families in every community where flanges are donated, with guidance on ensuring they are sanitized appropriately between people. This isn’t impossible; it just takes a few people to help make changes in their community. Because flange size matters and flange fitting can revolutionize pumping for parents and babies!



Julie Brill, IBCLC, CCCE, CLD, Faculty

Julie Brill has been training CAPPA labor doulas and childbirth educators for over 20 years. She has a busy private practice helping parents to feed their babies virtually and in person in Massachusetts. She also offers private, independent, virtual lactation and childbirth classes to pregnant families and virtual CAPPA trainings  for doulas and childbirth educators. Her virtual course Breastfeeding for Birth Professionals earns 3 CAPPA CEUs. Julie is the author of the doula anthology Round the Circle: Doulas Share Their Experiences and the mother of two adult daughters. Reach her at www.WellPregnancy.com.

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