Correct Fit of a Breast Shield

The breast shield is the part of the pump kit that fits over the nipple, the areola and part of the breast. It comes in a range of sizes. Not all women have the same size and shape of nipples and breasts.

Medela shields come in 21, 24, 27, 30 and 36 mm. Spectra shields come in 24, 28 and 32 mm.               

The Medela Symphony rental pump kit and the  Pump In Style come with 24 mm shields. The Medela Freestyle comes with 24 and 27 mm shields. The Spectra comes with 24 mm shields. 

What is a Correct Fit?

A breast shield fits if it is comfortable and removes milk well. Your nipple should easily move in and out of the tunnel (the narrow portion of the shield) with no pain.

When is a shield too small?

If your nipple rubs on the side of the tunnel and it hurts while you pump, or if you feel it is not removing milk well from your breasts, you may want to try the next larger size.

When is a shield too big?

If you notice that your areola is being pulled into the tunnel along with your nipple, and it hurts, you may want to try a smaller size shield.

Some women can use any size of breast shield and pumping is comfortable. Other women need to find the one size that works best for them. Most women 
would be fine with two or three different sizes.

Some women may use one size of breast shield on one breast and another size on the other breast.

Increasing the pressure (suction) too high on a pump may also result in nipple pain. You may have to adjust the pump pressure until you find what is most 
comfortable and removes milk best for you.