When you express breast milk with a breast pump, the device must fit correctly over the breast to form an effective seal. Because breasts come in a variety of sizes, most breast pumps have interchangeable breast shields or flanges in various sizes to ensure a proper fit. As you select a breast pump, choose a breast shield or flange in the correct size to ensure that the device works effectively to empty your breasts, suggests nurse Paula P. Meier, according to Medela.com.
Place the breast shield of the pump onto your breast, centering it precisely over the nipple. Turn the breast pump on.
Observe how the nipple moves within the tunnel of the breast shield – it should have enough space to move in and out without restriction, advises the Medela website. Choose a larger breast shield if the nipple is so large that it doesn’t move freely. Choose a smaller breast shield if the nipple is so small that the breast shield does not provide an effective seal.
Check the areola as the breast pump operates. The areola should not move into the tunnel of the breast shield. If it does, the breast shield is too large.
Monitor the sensations of pumping as you operate the breast pump. You should notice comfortable, rhythmic movement that effectively empties the breast. If you feel pain, it’s likely due to an improperly fitting breast shield or flange, suggests the Ameda website. Assess the fit to determine whether you need a smaller or larger breast shield.