Measure Nipple

The Importance of Choosing the Right Breast Pump Flange Size

Getting the correct breast pump flange size is crucial for a successful pumping experience. An ill-fitting flange can lead to a range of issues, including clogged ducts, discomfort, and pinching—none of which are pleasant.

Using a flange that is too small or too large can negatively impact your ability to pump effectively, making it essential to select the right size.

To assist you in making the best choice, we’ve provided a comprehensive flange sizing guide below. Ensure you get the optimal fit for a more comfortable and efficient pumping experience!

Which part should measure

A pink and purple circle with a green ball in balancing on the left bottom part of the ring.

Identify the nipple and aerola area

Take know are you have an elasticity nipple or not

Measuring from nipple to nipple base

Less then 1mm of areola for the exact size

Suggestion size

Blissbaby Flange Sizing Guidelines
Blissbaby Flange Sizing Guidelines

Add 0-4mm from exact nipple size.

STEP 1: Stimulate Your Nipple
Gently roll or massage your nipple for a few seconds to mimic how it looks when erect — this gives a more accurate size, like how it will appear during pumping.

STEP 2: Measure Nipple Diameter Only

  • Use a millimeter ruler or nipple sizing tool.
  • Measure only the nipple, not including the areola (the darker surrounding area).
  • Measure across the base of the nipple (widest part).
  • Example: If your nipple is 16mm in diameter, write that down or start from 0cm(1cm=10mm)

STEP 3: Add Buffer to Get Flange Size

  • Before pumping? ➕ Add 2–4mm
  • After pumping? ➕ Add 1–2mm
    💡 This gives room for comfort and nipple swelling during pumping. Suggestion to measure 1 hour after pumping

Example:
Nipple diameter = 16mm
Recommended flange size = 18mm or 20mm

But remember, it is normal if your breast size is different. Your breasts might need a different size flange; therefore, you might need to buy one for each. Even so, the size of your flange might fluctuate as you pump. To make sure you are still utilizing the right size, So it is recommended that you remeasure your flange size before replacing your breast pump parts. Suggestion to re-measure every 1-3 months. Generally speaking.

✅ SIGNS YOU’RE USING THE RIGHT SIZE:

  • Nipple moves freely inside the tunnel
  • Minimal areola is pulled in
  • No pain or rubbing
  • Good milk flow

PLEASE CONSULT WITH PROFESIONAL LACTATION COUNSELOR IF YOU’RE EXPERIENCE NIPPLE PAIN OR DAMAGE.

Impact

a white ball on a striped blue surface

Comfort and fit

Accurate measurements ensure a comfortable and personalized fit, reducing pain during pumping

The right flange size improves suction, leading to more efficient milk expression.

Proper sizing helps prevent complications like clogged ducts and mastitis