It's all about the fit
Boob maths: One size wearable pump + your personal size of insert or flange = a perfect fit package so you can express milk comfortably and effectively.
Let's get you measured up, follow the info below.
How to measure your nipple size
This is probably the first time you have had to distinguish between your nipple and areola and for most of us this is the first time we have had to place a measuring tape or ruler to our nipple.
Be sure to measure both sides, as nipple sizes can differ on each breast. For the perfect fit check the chart below to choose your insert or flange.
What size insert you'll need
Start here...
Fitting Guide Disclaimers
1. Size Recommendations Are Guidelines Only
The sizing chart and fitting guide provided are for general guidance purposes only. Every body is unique, and the recommended insert size may not be the perfect fit for every individual.
2. Measure Carefully
We strongly advise selecting an insert size that closely matches your actual nipple diameter. Accurate measurement (ideally when the nipple is warm and relaxed) helps improve comfort and pumping efficiency.
3. Fit Should Be Comfortable
The insert should not feel tight, constricting, or cause any pain while pumping. If you experience discomfort, irritation, or nipple blanching, stop use immediately and try an alternate size or consult a lactation professional.
4. Trial and Adjustment May Be Needed
Finding the right fit may require some trial and error. What works well for one mum may not work for another, even with similar measurements. Factors like breast tissue elasticity, nipple shape, and pumping frequency all play a role in fit.
5. Nipple Size Can Change Over Time
Nipple size can change throughout pregnancy and your breastfeeding journey. Please keep this in mind and recheck your nipple measurements regularly, especially if you experience changes in comfort or milk output.
6. Not a Substitute for Medical Advice
This guide is not intended to replace advice from a lactation consultant or healthcare provider. If you're experiencing ongoing pain, low milk supply, or concerns related to pumping or breastfeeding, please seek professional support.
7. Product Use Warning
Improper sizing and prolonged use of an ill-fitting flange or insert may lead to nipple damage, reduced milk output, or clogged ducts. Always monitor your comfort and pumping results, and adjust as needed.
10mm nipple
You'll need a 11mm insert
11mm nipple
You'll need a 12mm insert
12mm nipple
You'll need a 13mm insert
13 mm nipple
You'll need a 14mm insert
14mm nipple
You'll need a 15mm insert
15mm nipple
You'll need a 16mm insert.
16mm nipple
You'll need a 17mm insert.
17mm nipple
You'll need a 18mm insert.
18mm nipple
You'll need a 19mm insert. This insert size is compatible and included with our Viva Pro Breast Pump.
19mm nipple
You'll need a 20mm insert.
20mm nipple
You'll need a 21mm insert. This insert size is compatible and included with our Viva Pro Breast Pump.
21-23mm nipple
You'll need a 24mm flange. Good news, this size flange comes as standard in our Wearable Pump. This flange is also compatible with our Viva Pro Breast Pump.
24-26mm nipple
You'll need a 27mm flange. This flange size is only compatible with our Wearable Pump.
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