How do your breasts change during each phase of pregnancy? 

Pregnancy changes your body in so many ways, and your breasts are no exception. For many lactating parents, breast changes (aka swelling and soreness) are one of the first signs of pregnancy. Your hormones — specifically: estrogen, progesterone, and prolactin — are the driving force behind these changes, as they start working overtime to prepare your body for pregnancy, childbirth, and breastfeeding.

Breast changes during pregnancy are very common, but they’re not universal. Every person — and every pregnancy — is different. More importantly, those changes (or lack thereof) have nothing to do with your ability to breastfeed or chestfeed.

Now, let’s dig into the most common changes that people with breasts go through during each phase of pregnancy

First Trimester Breast Changes 

During your first trimester, you’ll probably notice your breasts growing and becoming sore. It’s normal to go up a bra cup size or two while pregnant, and that process can start almost immediately. In the early weeks of your pregnancy, your body starts producing more blood to pump nutrients and oxygen through your body and your baby’s. This increased blood flow can cause your breasts — including your nipples — to become swollen, tender, and tingly. It can also make the veins in your breasts bigger, bluer, and easier to see.

Second Trimester Breast Changes 

Your breasts will continue to get bigger throughout your second trimester as your milk ducts develop. This is when you may need to make the leap and transition to the next bra cup size. It’s also when you may notice your areolas start to get larger and darker. They may also begin to develop tiny bumps called Montgomery’s tubercles. These are totally normal! In fact, they exist to produce lubrication and make breastfeeding easier.

During the second trimester, your body also starts making a substance called colostrum that can look like a yellowish and thick nipple discharge. This is the first form of “breast milk” that your newborn will eat if you choose to breastfeed, and it plays an important role in boosting their immune function in the early days of breastfeeding.

For many, breast changes (aka swelling and soreness) are one of the first signs of pregnancy.

Third Trimester Breast Changes   

Your third and last trimester will bring more of the same breast changes as the first two. You’ll notice your breasts continue getting bigger, heavier, and denser, which may lead to stretch marks. You may also experience some itchiness or dryness as your skin stretches to accommodate your breast growth. (Moisturizer is your friend!)

During your third trimester, more colostrum may start leaking from your nipples. You’ll continue producing colostrum until a few days after your baby is born. Then — thanks to a sharp drop in estrogen and progesterone, accompanied by a rise in prolactin — your body will switch to making milk.

The changes your breasts experience during pregnancy are part of how your body prepares to care for your baby. You’ve got the internal prep under control, but the external prep — aka getting your home ready for a newborn — may be a different story. That’s where the Juno Birch™ Fetal Gender Test comes in. 

With our at-home test, you can find out the sex of your baby as early as week 7 of your pregnancy, so you can get a jump start on decorating the nursery, picking out clothes, and imagining what the future looks like for your growing family. Click here to learn more about our Juno Birch™ Fetal Gender Test.

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September 30, 2022 — Stephanie McClintock