When it comes to using a breast pump, the size of the flange you use can make a significant difference in both your comfort and the effectiveness of the pump. This is especially true for Zomee pumps, where the right flange size ensures optimal suction strength and milk output. In this blog, we'll discuss why using the correct flange size is crucial and how Zomee helps you find the perfect fit.

Why Flange Size Matters

The flange, also known as the breast shield, is the part of the pump that fits directly on the breast, over your nipple and areola. Using the wrong size flange can lead to several issues, including:

  • Reduced Suction Strength: If the flange is too large or too small, it can compromise the suction, making it difficult to express milk efficiently. Proper suction is essential for maintaining your milk supply and ensuring effective pumping sessions.
  • Discomfort and Pain: If the flange does not fit correctly, it can cause pain, irritation, and even damage to the nipple. Comfort is key to successful and consistent pumping.
  • Blocked Milk Ducts: Incorrect flange size can lead to incomplete emptying of the breast, increasing the risk of blocked milk ducts and mastitis.

Identifying the Right Flange Size

Finding the right flange size starts with measuring the diameter of your nipple (not the areola) and adding 0-3 millimeters to determine the optimal size. Zomee includes a nipple ruler to make measuring simple and accessible at home.

Flange sizes typically range from approximately 15mm to 24mm, but comfort and effectiveness are just as important as the measurement itself. Your ideal size is one that allows your nipple to move freely in the tunnel without rubbing, pulling in too much areola, or causing discomfort. 

Flanges vs. Inserts: What’s the Difference?

While the terms are often used interchangeably, flanges and inserts serve slightly different purposes, and understanding the difference can help you achieve a better fit.

  • Flanges are the (hard plastic) full breast shield that connects directly to the pump. They come in specific sizes and determine the overall fit against your breast.
  • Inserts are soft, flexible silicone pieces that sit inside a standard flange to fine-tune the fit by reducing the tunnel size.

Zomee wearable pumps come with inserts, giving moms more flexibility to adjust sizing without needing to immediately swap out the entire flange. Inserts are especially helpful if you’re between sizes, notice changes over time, or want a more cushioned, customized feel. Using the correct combination of flange and insert can significantly improve comfort and pumping efficiency. This can be helpful for pumpers with elastic nipples that touch the end of the flange tunnel – in this case we recommend sizing down for the best results.

Our Zomee Z2 Double Electric Breast Pump comes with 4 flange sizes 17mm, 19mm, 21mm and 24mm. It is the most offered by any brand!

Zomee’s Perfect Fit Promise™  

At Zomee, we know every body and every breastfeeding journey is unique and that the right fit is essential for a comfortable and effective pumping experience. That’s why Zomee offers one of the widest ranges of flange sizes available and includes more size options with our pumps than any other brand.

We stand behind every pump with our Perfect Fit Promise™: if you find that you need a different flange size than what’s included, simply let us know. We’ll send you a FREE pair in the size you need, with no hassle and no additional cost. Because supporting mothers means honoring individual needs and ensuring you feel confident, comfortable, and supported every step of the way.

Customer Testimonials

Many mothers have benefited from using the correct flange size with their Zomee pumps. Here are a few testimonials: 

"I was struggling with low milk output until I tried the right flange size with my Zomee pump. The difference was incredible, and pumping became so much more comfortable!" - Jessica L.

"The complimentary flange sizing from Zomee made all the difference for me. I found the perfect fit, and now my pumping sessions are efficient and painless." - Emily R. 

“I was stressed about which size I was and [Zomee’s] team handled me in such a kind and loving way. Zomee is the company every mom needs in their feeding journey.” – Naomi M.  

Conclusion

Using the correct flange size is essential for comfortable, effective pumping. When moms have the right fit, pumping feels more natural, efficient, and supportive of their breastfeeding goals.

Zomee supports this experience through inclusive sizing, built-in inserts, and the backing of our Perfect Fit Promise™, so moms can feel the most confident. To learn more about Zomee pumps or get help with sizing, visit the Zomee website or reach out to The Mom Line™ - our support team of mothers and lactation consultants - who are always available to offer guidance and support.

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