Finding the right fit is crucial, whether for clothing, shoes, or your breast pump flange. Many breastfeeding moms struggle with maximizing milk output during pumping sessions without realizing the problem often lies in their flange size. Using the correct flange size enhances milk production and ensures comfort during pumping by stimulating the breast effectively.

What Is a Breast Pump Flange?

A breast pump flange, or a breast shield, is a cone-shaped plastic cup designed to fit over the nipple and create a seal around the areola. When the vacuum suction activates, it gently draws the nipple into the flange’s tunnel to extract milk. A poorly fitting flange can disrupt milk flow and damage delicate breast tissue, leading to pain, swelling, and reduced milk output.

How Does Flange Size Impact Pumping?

The flange mimics a baby’s latch during breastfeeding. If it’s too large, the areola gets compressed, much like a kink in a water hose, preventing milk from flowing correctly. A flange that is too small creates excessive friction on the nipple, leading to discomfort, blisters, and inefficient milk production. The right fit ensures that pumping sessions are both productive and pain-free.

How to Place a Breast Pump Flange

When using a breast pump flange, ensure your nipple sits centrally in the tunnel without touching the sides. This alignment allows the nipple to move freely and stretch naturally during pumping. Proper placement minimizes stress on the breast, promotes effective milk extraction, and helps the body respond well to oxytocin, the hormone responsible for milk letdown.

Understanding Nipple and Areola Dynamics

The flange doesn’t only interact with the nipple; the areola also plays a role. During breastfeeding, a baby latches onto the nipple and part of the areola, stimulating milk ducts effectively. Similarly, the flange should draw in the nipple and a small portion of the areola to mimic this natural process. Inadequate stimulation can lead to reduced milk supply over time and discomfort during pumping.

How to Measure Your Nipple for Flange Sizing

To determine your flange size, measure the diameter of your nipple (not including the areola) in millimeters. Here’s a quick guide:

  • Up to 17mm: Use a 21mm flange.
  • 18-22mm: Use a 24mm flange.
  • 23-26mm: Use a 27mm flange.
  • 27-30mm: Use a 30mm flange.
  • 31-32mm: Use a 36mm flange.

Once you’ve measured, test the fit during a pumping session. Look for a comfortable movement of the nipple within the tunnel without excessive contact with the sides.

Signs Your Flange Size Is Correct

  • Your nipple is centered in the flange and moves freely without friction.
  • Your breasts feel fully drained after pumping.
  • You experience no pain or discomfort during or after pumping.
  • Your nipple and areola maintain normal coloration.

How to Tell If Your Flange Is Too Small

A flange that’s too small can cause:

  • Friction against the nipple, leading to soreness or cracking.
  • Pinching or squeezing sensations during pumping.
  • Blocked milk ducts and reduced milk flow.
  • Nipple discoloration due to restricted blood flow.

How to Tell If Your Flange Is Too Big

If your flange is too large, you may notice:

  • Most of your areola is being pulled into the tunnel, causing pain.
  • A loss of suction seal during pumping.
  • Inadequate breast drainage, leading to reduced milk output.
  • Discomfort or discoloration of the areola.

When to Reassess Your Flange Size

Flange size isn’t static; it can change over time. Factors like pregnancy, postpartum recovery, and fluid retention can alter nipple size. For most women, measuring in the third trimester or a few weeks postpartum provides an accurate fit. However, regular reassessments are important, especially if you experience discomfort or changes in milk production.

Bonus Tips for Finding the Right Flange Size

  • Consult a lactation consultant for guidance on flange fit and pumping techniques.
  • Measure both nipples—sizes can differ between breasts.
  • Remember, flange sizes might need adjustment over time.

Getting Help From an Expert

If you need clarification on your flange size or help with pumping, contact an International Board-Certified Lactation Consultant (IBCLC). They can provide personalized advice on flange fit, troubleshooting, and optimizing your pumping experience.

With the right flange size, you can make your pumping journey more comfortable and effective, ensuring you meet your breastfeeding goals.