The breast pump flange (or breast shield) is the funnel-shaped piece that fits over the nipple and areola, creating a vacuum seal for milk expression. This component is integral to comfortable and efficient pumping, but its size is not static. Flange size requirements frequently change over time. This fluctuation is a normal biological response to postpartum changes and the physical mechanics of consistent milk removal. Understanding these shifts is important for maintaining comfort and maximizing milk output.
Why Proper Sizing Is Critical
Using a correctly sized flange is tied to both physical comfort and effective milk removal. A flange that is too small can cause the nipple to rub against the sides of the tunnel, leading to painful friction, swelling, and potential skin damage. This irritation can cause bruising or cracking, which may discourage continued pumping.
Conversely, a flange that is too large allows too much of the areola to be pulled into the tunnel, which compresses milk ducts and inhibits flow. When milk ducts are compressed, the breast is not thoroughly drained, signaling the body to decrease milk production. An ill-fitting flange compromises the vacuum seal necessary for the pump to function efficiently. Inefficient milk removal can also contribute to complications like blocked milk ducts or engorgement.
Factors That Cause Changes Over Time
The need for a different flange size is driven by physiological changes occurring after childbirth. One immediate factor is the receding of postpartum edema or generalized swelling. Nipple size often peaks immediately after birth, partly due to swelling from intravenous fluids, and then gradually decreases as the body regulates fluid balance.
Hormonal shifts as the milk supply regulates also influence tissue characteristics. The milk supply transitions from hormone-driven to supply-and-demand driven, typically stabilizing around 6 to 12 weeks postpartum. This settling of hormones can lead to a gradual reduction in nipple size.
Consistent mechanical action from the pump also plays a role in tissue elasticity. Prolonged or frequent pumping can alter the elasticity of the nipple and areola complex. Some individuals observe a change in the shape or size of the nipple due to repetitive stretching, potentially requiring a smaller flange size as the tissue becomes more pliable.
Signs You Need A Different Size
Recognizing the signs of a poor fit is important for preventing discomfort and maintaining milk output. One clear visual cue is observing how the nipple moves inside the flange tunnel while pumping. The nipple should be centered and pulled gently into the tunnel without excessive rubbing against the sides. If the nipple appears compressed, rubs vigorously, or if the areola is pulled significantly into the tunnel, the size is likely incorrect.
Discomfort or pain during or immediately after a pumping session is a major indicator that the flange size needs adjustment. Look for specific visual changes to the nipple tissue, such as blanching, where the nipple tip turns white due to restricted blood flow. The nipple may also appear red, swollen, or irritated after pumping, suggesting friction or excessive pressure.
Functional signs are equally important and relate directly to the pump’s effectiveness. A noticeable decrease in the volume of milk expressed during typical pumping sessions can signal that the flange is no longer efficiently draining the breast. If the breasts still feel full or heavy after a pumping session, it suggests that milk removal is incomplete, a common consequence of an ill-fitting flange.
How to Re-Measure For Optimal Fit
The process for re-measuring should occur when the nipple is in a stimulated state. Since the nipple stretches during milk expression, the most accurate time to measure is immediately after a pumping session. Use a flexible measuring tool or ruler to determine the diameter of the nipple across its base, where it meets the areola. The measurement should be taken in millimeters and must not include the areola tissue.
To determine the appropriate flange size, add a few millimeters to the measured nipple diameter. The goal is to select a flange slightly larger than the nipple, typically by 1 to 4 millimeters, to allow for comfortable movement inside the tunnel. Always check the specific sizing charts provided by the pump manufacturer, as the recommended allowance varies between brands.
It is recommended to measure each side separately, as many individuals have different sized nipples that may require different size flanges. The final check for a proper fit is to observe the nipple movement during a pumping session at a comfortable vacuum level. The nipple should move freely back and forth within the tunnel, and only a small amount of the areola should be drawn in with each cycle.