A breast pump flange is the funnel-shaped part of the pump that creates a seal around the areola and draws the nipple into its tunnel to extract milk. Choosing the correct size is a common challenge for many users, yet it is a necessary step for comfortable and efficient milk expression. An improperly sized flange can lead to pain, tissue damage, and ultimately, a reduced milk supply. The right fit ensures maximum milk output and minimizes the risk of injury.
Initial Steps: How to Measure and Choose a Flange Size
Determining an initial flange size requires measuring the nipple diameter before pumping begins. Focus specifically on the nipple width at its base, where it meets the areola, and not the areola itself. This measurement should be taken in millimeters, using a ruler, measuring tape, or a specialized sizing tool.
It is helpful to gently stimulate the nipple before measuring to ensure it is fully extended, but avoid measuring immediately after a feeding session. Since nipple size can vary between breasts, measure both sides independently. This acknowledges that you may need a different size flange for each breast.
Once the nipple diameter is determined, add an additional clearance of 1 to 3 millimeters to select the starting flange size. For example, if your nipple measures 17 millimeters across, a flange size of 20 or 21 millimeters is the appropriate starting point. This allowance accounts for the natural expansion of the nipple tissue that occurs when suction is applied.
The Dynamic Check: Visualizing Proper Nipple Movement
The ultimate test for a correct flange size is observing the nipple’s movement and appearance while the pump is actively running. A properly fitted flange allows only the nipple to be drawn deep into the tunnel, along with perhaps a very small portion of the areola. The nipple should move freely back and forth within the tunnel with each suction cycle without rubbing against the sides.
During the pumping session, the nipple should appear elongated but should not swell dramatically or show signs of restriction. The color of the nipple and areola should remain consistent with its color before pumping. Blanching, or turning white, is a clear sign that the flange is too small and is compressing the tissue.
The nipple should not look bruised, deep purple, or excessively reddened after the session is complete. The visible movement should be a gentle, rhythmic gliding motion without excessive friction or pain. If the nipple is sticking to the sides or seems to be pulled completely to the end of the tunnel, the fit is likely incorrect, compromising efficient expression.
Consequences of Improper Flange Fit
Using an incorrectly sized flange can lead to immediate discomfort and long-term issues with milk production. If the flange is too small, the nipple will rub painfully against the sides of the tunnel, creating friction. This friction can result in nipple damage, such as blistering, bruising, or cracking, and the compression restricts milk flow.
The constriction from a too-small flange can prevent the milk ducts from fully emptying, potentially leading to clogged ducts and reduced milk yield. Conversely, a flange that is too large allows too much of the areola to be pulled deeply into the tunnel along with the nipple. This excessive pulling can cause a tugging sensation and may lead to tissue swelling.
When the areola is pulled too far, it compromises the vacuum seal and reduces the pump’s suction efficiency. Swelling in the areola can mimic the symptoms of a flange that is too small, creating a cycle of discomfort and poor milk removal. Inadequate milk removal, resulting from either poor fit, can signal the body to decrease milk production over time.