By moms. For moms.

How Will Pregnancy and Nursing Affect My Bra Size?

How Will Pregnancy and Nursing <br> Affect My Bra Size?

How will pregnancy and nursing affect my bra size?

Since moms often ask our Customer Care team if they really need different bra sizes for different stages of pregnancy and nursing, our Customer Service Manager Hannah wanted to share some Kindred Bravely moms’ experiences with fluctuating breast size.

When I was pregnant with my son seven years ago, I was surprised to find that as I entered my third trimester, my bras became unbearably uncomfortable (as many things become in the third trimester). The underwire poked me, the band was too tight, and I started fantasizing about wearing a sports bra to work every day. Unable to deal with the constant discomfort, I ran to a department store and bought my very first underwire-free bras. They were in odd colors and a size I had never even looked at before, but they were a dream compared to my ill-fitting pre-pregnancy bras.

how will pregnancy affect my bra size?

Just a couple of days before I gave birth, I ordered a nursing bra online, making my best guess on size but having no idea how my size would change once my milk came in. A few days after I delivered, my mom kindly pointed out that my breasts had grown larger than my baby’s head, so a supportive, functional bra was a must. The bra I bought online was close to the right size, but I definitely needed more support. I had been wearing a 36D for several years before getting pregnant. At the end of my pregnancy, I was a 40DD/E. In the early days of nursing, and for much longer than I expected, my size hovered at a 38I and eventually settled at a 38G. I’m currently nursing my second child who is two years old, and I wear a 36DD/E.

For most women, size fluctuation is completely normal and almost impossible to predict. I asked a few Kindred Bravely moms how their size changed during pregnancy and through nursing.

Our Production Manager Pratyasha wore a 32C pre-pregnancy. Once she gave birth to her son six years ago, she was a 38D/40C. Years after weaning, she now wears a 34C.

Kindred Bravely’s Marketing Manager Stephanie also wore a 32C pre-pregnancy. She grew to a 34C then a 36B at nine months pregnant. While nursing her son, she went through sizes 34DDD/F, 34D, and 32D. She is now back to a 32C.

Our Pinterest Manager Shantel wore a 32D pre-pregnancy. By the end of pregnancy, her size was 36DD. Three weeks postpartum, her breasts were full of milk and up another cup size. When her baby’s nursing slowed down around 12 months, her cup size had leveled out, and her rib cage had returned to its pre-pregnancy measurement, leaving her at a 32E.

How will nursing affect my bra size?

I asked Shantel, who is also an IBCLC and nurse, about typical changes in bra size during pregnancy and nursing. “We know through research and observation that a woman’s body makes incredible changes in order to sustain and grow a tiny human,” Shantel said. “Internal organs including the stomach, liver, and intestines shift upwards as the uterus grows outwards. To make room for these shifted organs, the rib cage expands. During pregnancy, milk ducts form, vascularization increases, nipples become more erect, areolas become darker and larger, and Montgomery glands enlarge. These changes lead to breast growth, which can affect breast shape and size (a woman’s breasts nearly double in weight during lactation).”

While the exact fluctuations vary from woman to woman, I wondered if there was a typical time frame for milk supply (and thus breast size) to become regulated. Women often experience a large change as their milk comes in 3-5 days postpartum. Shantel says that breast fullness levels off as a supply-and-demand breastfeeding relationship is established. “A woman’s breasts usually decrease in size around 6-9 months while her milk production levels remain constant.” Exactly when this happens is different for everyone and can even vary for each pregnancy a woman has.

how will nursing and pregnancy affect breast size?

Given the magnitude of changes that occur during pregnancy and nursing, it’s impossible to guarantee that one bra will fit throughout the whole journey. We recommend that you order bras as close as possible to when you'll wear them and that you measure before ordering to ensure you’ll get the best fit. You may find yourself comfortable in one size in the first and second trimesters, needing a larger size in the third trimester, and then again experiencing fluctuations after giving birth. The good news is that once your milk supply is established and a consistent nursing relationship with your little one is in place, your size will likely regulate as well.

If you have any questions about fit, reach out to the Customer Care team on Facebook Messenger, live chat here on our website, or email at

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