Breast Shields – Choosing The Right Sized Breast Shields

When it comes to breast pumping and finding the right breast pump, one of the most important aspects is often times overlooked. Of course the breast pump should be powerful, with plenty of CPM’s, and yes it should be easy to use and easy to clean, and yes it should be durable. All these things are important when it comes to the effectiveness of your breast pump, but without the right sized breast shields, it won’t be effective. The right sized breast shields will allow you to fully empty your breasts and offer maximum milk output when pumping.

How can you tell if the breast shields are too small?

Breast Shields - Correct Fit

Breast Shield – Correct Fit

Breast shields, also known as a flanges, are shaped like a funnel with a cup on one end and a small tunnel on the other end called the nipple tunnel. The size of a breast shield really has nothing to do with the size of the breast, it’s all about the size of the nipple. In fact, when you see a size listed, like the 24 mm breast shields, that means that the nipple tunnels are 24 mm, not the cup. In order for breast shields to fit correctly, the nipple must sit in the center of the tunnel, and as it’s drawn into the tunnel with the vacuum, it should move freely, not rub on the sides of the tunnel. You may notice soreness on the outside of your nipple, not the tip. You may also notice skin flecks left inside the breast shields nipple tunnel, this should not happen. If any of this sound familiar, your breast shields may be too small.

Breast Shields - Too Small

Breast Shield – Too Small

You see, a breast pump is responsible for mimicking your baby’s sucking rhythm, and the breast shields are responsible for mimicking your baby’s latch. There are small ducts inside your nipple that upon milk ejection, or let down, will fill with milk. Only the right kind of stimulation will allow these ducts to open and release your breast milk. If the breast shields fit too tightly, they may squeeze those ducts, keeping them from opening fully and releasing your breast milk. Overtime those ducts could plug up and lead to mastitis, inflammation in the breast that causes severe pain, or even a drop in your milk supply.

How can you tell if you breast shields are too big?

Breast Shields - Too Big

Too Big

Having breast shields that are too big is not quite as common as having breast shields that are too small, however here are a few things to look for. First of all, do you feel any pain or discomfort around the areola during pumping? If too much of your areola is being pulled into your breast shields with your nipples, or if the tip of your nipple is sore because it’s being pulled too far into the tunnel and hitting the end, then your breast shields are too big.

Which breast pumps offer different sized breast shields?

Nipple sizing or breast shield sizing may be the deciding factor when it comes to choosing a breast pump. Not all breast pumps offer different sized breast shields. Some only offer one size fits all. So, before you choose a breast pump, take a look at your nipple and try to decide if you’re average sized or larger than average. This question is hard to answer without physically seeing your nipple being pulled into the nipple tunnel, however, you can measure yourself with a ruler just to get an idea. Nipple tunnel sizes range from a small 21 mm, standard 24 mm, large 27 mm, and extra large 30 mm. Measure the width of your nipple, not including the areola.

Breast pumps that offer different sizes of breast shields are the Medela’s, and the Ameda’s. The Phillips AVENT and Lansinoh breast pumps offer one size fits all.

Check out this list of manual, single, and double electric breast pumps, including the Medela Pump In Style, Medela Freestyle, and Ameda Purely Yours.

Best Breast Pumps – From Manual To Electric


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