A breast pump flange, sometimes called a breast shield, is the cone-shaped plastic or silicone tunnel that fits over the nipple and areola during a pumping session. This piece creates the vacuum seal necessary for effective milk expression. The right flange size is a requirement for both comfort and efficiency, ensuring that milk is removed effectively and completely. Selecting the correct flange size significantly improves the pumping experience.
The Importance of Proper Flange Sizing
Using a flange that is incorrectly sized can lead to a host of negative outcomes, impacting both the body and the overall milk supply. When a flange is too small, the nipple may rub painfully against the sides of the tunnel, which can cause friction, swelling, or blistering. This compression can also interfere with the milk ducts, reducing the flow and leading to inadequate drainage.
Conversely, a flange that is too large allows excessive areola tissue to be pulled into the tunnel, causing a tugging sensation and discomfort. When the breast is not emptied thoroughly due to an improper fit, the body can receive a signal to decrease milk production over time. Ineffective milk removal also increases the risk of complications such as clogged ducts and mastitis, making accurate sizing a necessary step for maintaining breast health.
Step-by-Step Guide to Nipple Measurement
Accurately measuring the nipple is the first step toward selecting the correct flange size. It is best to perform this measurement after a pumping or feeding session, as the nipple is typically fully distended. You will need a standard ruler or a specialized nipple sizing guide, and all measurements should be recorded in millimeters (mm) for precision.
The goal is to measure the diameter of the nipple base, which is the width of the nipple where it meets the areola. Measure only the nipple itself, not the surrounding darker areola tissue. Place the ruler or measuring tool across the widest part of the nipple and record the measurement.
Since it is common for the breasts to be slightly asymmetrical, it is necessary to measure both nipples separately. It is not unusual for a person to require two different flange sizes to achieve the most comfortable and effective pumping experience. Keep in mind that the nipple size can fluctuate throughout the pumping journey, so re-measuring may be required if comfort or milk output changes.
Selecting and Verifying Your Flange Size
Once the base measurement is obtained, a conversion rule is applied to determine the final flange size. Standard guidance is to take the measured nipple diameter and add 2 mm to 4 mm. This addition accounts for the natural expansion of the nipple tissue during pumping and allows for free movement inside the tunnel. For example, a nipple measuring 17 mm typically requires a flange size between 19 mm and 21 mm.
The final step is to verify the fit during an actual pumping session, as this visual check confirms the measurement’s accuracy. With the pump on, the nipple should be centered in the tunnel and move freely without friction or rubbing against the sides. The areola should not be pulled excessively into the tunnel, which indicates the flange is too large.
If the flange is too small, the nipple may swell or turn white, and little milk may be expressed. If the flange is too large, suction may feel ineffective, and milk output may decrease. A well-fitting flange will feel comfortable and result in complete breast drainage.