How to Choose the Right Breastshield Size for Pumping

Quick answer

The right breastshield size depends on your nipple diameter. Measure your nipple at the base (not the areola) and choose a shield 1-2 mm larger for a comfortable, efficient pump session.

How to find your correct breastshield size

1. 1. Measure your nipple diameter: Use a ruler or measuring tape to measure the width of your nipple at its base (not the areola) after a pumping session or after feeding, when it is most extended. Write down the measurement in millimeters. Common mistake: measuring the areola instead of the nipple. Focus on the nipple base only.
2. 2. Choose a shield 1-2mm larger: Select a breastshield that is 1-2mm wider than your nipple measurement. For example, if your nipple is 22mm, a 24mm shield is a good starting point. Many brands like Medela offer sizes in 4mm increments, so round up if needed. Checkpoint: If your nipple rubs against the tunnel walls or your areola is pulled in excessively, the shield is likely too small or too large.
3. 3. Test the fit during a pumping session: Attach the shield and pump at your usual suction level. Your nipple should move freely in the tunnel without touching the sides. There should be no pain, and your areola should not be drawn into the tunnel more than a few millimeters. Common mistake: ignoring mild discomfort. Even slight pinching can reduce milk output over time.
4. 4. Adjust if you see signs of poor fit: If you experience pain, reduced milk flow, or notice redness after pumping, try a different size. Many manufacturers sell individual shields, so you can buy one size up or down without replacing the whole set. Checkpoint: A properly sized shield should feel comfortable throughout the session and leave no marks or indentations on your nipple.

Product facts

• Medela PersonalFit Flex Medium Breastshield 24mm: The Medela PersonalFit Flex Medium Breastshield has a 24mm diameter, designed for many Medela breast pumps with a flexible edge contour for improved comfort. If your nipple measures around 22-23mm, this 24mm shield offers a comfortable fit that supports efficient pumping without excessive friction.