Can Your Bra Cause Mastitis?

Can Your Bra Cause Mastitis?

By Dr. Kathleen F. McCue, FNP-BC, IBCLC-RLC

Making the best decision on bras, for your ideal breast health, does not need to be complicated. In fact, there are already too many rules about what moms need to do. In browsing the internet, I stumbled across an ad from a bra company that makes bra-wearing so formulaic that even I was stumped, and I’ve been helping women for many decades. I can only imagine what a new mom, already overwhelmed with taking care of baby, pumping, breastfeeding, etc., must be feeling.

This blog is being written to simplify things and offer the reader an easy explanation for what causes clogged ducts that could lead to mastitis and, what one should look for in a bra to protect your breast health.

What is mastitis? 

Mastitis is a condition that involves inflammation of the breast tissue, usually caused by an infection.

Causes of mastitis can be varied but typically are due to too much pressure from the outside, on one area of the breast. Plain and simple, a bra that’s too tight could cause a plugged (clogged) duct to form. If your bra has an area that compresses too much on your milk ducts it could literally dam up the milk flow. The milk then stagnates (so thickens) around the dam and your breasts begin to ache.

A secondary reason for mastitis is pressure coming from the inside of the breast from incomplete emptying, skipping a feeding or sleeping through a feeding.

A third reason is nipple damage offering bacteria an easy way of getting up into the breasts. If you have nipple trauma you want to wear a bra that would give you enough space for a breast pad or soft shell to be worn over the nipple. This can occur when babies begin to teeth around 3-12 months of age, so is not just for the early days when you and baby are practicing latch.

Going back to the issue of bra fit, many bras I see worn by women coming into my practice are simply too tight in the cup area. The problem gets worse when I see bras designed for pumping. Yes, you need compression to support your breast pump suction, however, there is a fine line between support for your pump and too much compression on your milk ducts as your breasts go through normal fluctuations in size throughout the day. Think about it, as your pump containers gets heavier with expressed milk, your breasts get smaller and softer, which means you no longer fill out the volume of the bra cup capacity as well as when your breasts were engorged. If you are wearing a bra that is still tight in the cup, when your breasts are empty, it is certainly much too tight and compressive when your breasts are full.

I recommend Simple Wishes nursing and pumping bras to my patients because their designs prioritize your breast health equally with the convenience of hands-free pump support. In their all day wear styles, their unique Comfort Sling accessory is a game-changer for women who are over producers or who prefer to use their pumps on low suction levels. This accessory is usually unnecessary for women who pump less than 2-3 ounces at a moderate suction level. The Comfort Sling attaches to the outer layer of the bra cup and uses the neckline of the bra as extra support to maintain suction on your pump. It allows you to position the bottles properly while giving you a low compression fit that is appropriate for all day wear. Here is a video tutorial, SuperMom Bra 101, showing how to use the Comfort Sling.

Mastitis Prevention Strategies

  • Wear a supportive bra that will keep the nipple lined up between your shoulder and your elbow.
  • Avoid too much compression in the cup area.
  • Research recommends COLD compresses, gentle expression or nursing and anti-inflammatory meds like ibuprofen. In the past we used to use heat and over-pump but now we know better.
  • Your breastfeeding journey is likely going to involve more than one bra size. Think about it like your skinny jeans and then the ones you might wear right after the holidays. You should be prepared with multiple sizes or styles of bras and, most importantly, measure yourself to make sure you are getting the correct fit. At a minimum you are going to need:
    • A bra that is comfortable while you are pregnant. I love Simple Wishes Undercover T-Shirt Bra because of it's transitional use. You can hide the nursing clasp while you are pregnant and then convert it for nursing function once you give birth. If you measure yourself in your 8th month of pregnancy, this will likely be the same size you will wear 6-8 weeks postpartum.
    • You will likely need another size to carry you through the first 0-8 weeks postpartum when you will maximize your potential for milk production and are very engorged.
    • Another size for beyond 8 weeks postpartum. This could be the same size you were wearing when you were 8 months pregnant. You will notice that although your breasts are smaller and softer than the first few weeks, they are still maintaining the appropriate supply for your baby.

    Most women, without even factoring in the bodily changes from pregnancy and breastfeeding, are wearing the wrong bra size. In fact, 88% of women in Simple Wishes test wearing groups did not measure themselves and guessed at their bra size. This resulted in 20% having to exchange for an alternate size. It is never a good strategy to guess your size or base your nursing bra size from your pre-pregnancy bra or an older bra that fits well. An older bra, that has worn down and stretched out could fool you into believing your bra size is smaller than today’s reality.

    Bra shopping online could start to feel like you are trying to hit a bullseye blindfolded but it doesn't need to be. There are two key factors to understand that will eliminate the confusion. First, spending a couple dollars for a flexible tape measure is a good investment that will empower you to make better decisions to positively impact your breast health. It will also save you the frustration of exchanging for alternate sizes. Second, pay attention to the measuring guide for each bra brand you are considering. Do not assume every bra brands measuring guide is the same. For example, some base their band size off your exact physical underbust measurements, others (like Simple Wishes) use the traditional method of your physical underbust measurements + 4 inches while others recommend measuring directly under the armpits to get a correct band size. None of these measuring methods are incorrect, you just need to be aware which method to use when considering each individual brand. To get your cup size, almost all brands recommend measuring over the largest part of your breasts and then doing some simple math to get your cup size. Simple Wishes has a fit quiz that makes this process very easy with no math required. Simply measure yourself, input your measurement and their quiz will tell you your appropriate bra size.

    In terms of styles of bras, here is an easy chart I use with my patients based on stage (pregnant, early postpartum or later postpartum) and feeding method (exclusive breasfeeding, combo breastfeeding + pumping or exclusive pumping) within Simple Wishes catalog of bras.

    Simple Wishes Bra Guide by Stage and Preferred Feeding Method

    Keep in mind, breasts are fraternal, not identical twins, so don’t expect them to be the exact same size and contour; always accommodate the larger one. Although nursing bras are now much better looking than in years past, they should still be practical and accomplish the primary goal of supporting your breasts. When a bra is not fitted properly, you’ll get too much “jiggle” which could stimulate milk supply adding to their weight resulting in increased pressure which is a cause of mastitis. Rethink jogging in the early months.

    Let’s talk about underwire. There is the misconception that underwire is the kiss of death in nursing bras. The issue is not the wire, it’s the fit of the wire. If you choose to wear an underwire bra, just make sure it completely surrounds your breast tissue and doesn’t compress in one area when your breast is at its most engorged state. This is often very hard to find, especially in the early weeks postpartum, when your breasts are in a significant state of change as your milk supply regulates to the needs of your baby. If you do plan to wear an underwire bra, I recommend waiting at least 6-8 weeks postpartum. Remember, the key to avoiding clogged ducts is proper fit whether you are wearing a wire free or underwire bra.

    Braless?  Not my favorite idea, as we have ligaments that form a natural bra and when our milk comes in, it can stretch them. Once those ligaments stretch there is no exercise that will snap them back into shape. For most women, the breastfeeding phase of life means your breasts are larger and heavier than they have ever been. Support is your best friend to prevent gravity taking a toll too soon.

    Bottom line is that you need a few different sizes of bras, and keep in mind that NO bra (in and of itself) will prevent mastitis. They WILL offer proper support which will help you be more comfortable, offer a way to hold pads in place and avoid targeted pressure which can cause plugs to form. The key is getting the right fit, and maintaining the right fit, as your body changes during maternity and postpartum. Understand your ideal fit by taking Simple Wishes Fit Quiz today!