How to Choose the Right Sized Breast Shield

The breast shield is that plastic funnel that you place over your breast to express your milk with a breast pump. Everybody is different, and we have all different size breasts and nipples. Sometimes we even have two different size breasts or nipples! The moral of the story – one breast shield size does not fit all. That's why Zomee offers you three different breast shield sizes.

Incorrectly sized breast shields can lead to soreness, blocked milk ducts, and impact milk production. When mothers experience an issue with breast pump suction, in many cases, it’s actually due to having the incorrect flange size. Having correct contact with the nipple and breast tissue is incredibly important for having proper suction.

The Zomee Double Electric Pump includes 24mm and 28mm breast shields in the box. 32mm breast shields are available to purchase at our store.

Determining your breast shield size

  • The first step to success involves determining the best breast shield size based on the diameter of your nipple. The standard size is 24mm, but you may need a larger size.

  • Use our Nipple Measurement tool to determine the diameter or the width across the base of your nipple. Do not include the areola or outer edge.

  • Place your nipple at the edge of the paper ruler and slide the top page to the other side of it. Where the top sheet ends determine your nipple diameter.

    Hint: 1 cm = 10 mm

Test your breast shield fit

Since your breast shield size is also dependent on breast tissue and skin elasticity, it’s important to confirm you’ve chosen the correct size. Here’s how to check:


Using the 24 mm breast shields included with your pump (or the size chosen after measuring your nipples), center your nipple and gently hold the breast shield against your breast. (Note: pressing breast shields too hard against your breasts when pumping can block your milk ducts.)


  • During pumping your nipple is able to move freely in the breast shield tunnel.

  • You have space around your nipple and not much of the areola is drawn into the tunnel with the nipple.

During pumping some, or your entire nipple rubs against the sides of the breast shield tunnel.

During pumping your areola is drawn into the breast shield tunnel.

You may experience your areola rubbing up against the side of the breast shield tunnel.