By: Amanda Hunt, expert bra designer + breastfeeding mom of 3

One of the very first signs of pregnancy for women has nothing to do with cravings or morning sickness. It starts with your breasts.

If you are newly pregnant and your breasts are starting to feel sore and tender to touch, fuller and heavier in size, rest assured this is normal!

As a bra designer and mom of three, I can tell you breast changes are one of the biggest physical transformations women experience during pregnancy, but also one of the least talked about. For first-time moms, this can honestly feel alarming, not knowing what is happening with your body during pregnancy. So let’s walk through breast changes by trimester, what’s normal, and how to stay comfortable through it all.

Why Do Breasts Get Larger During Pregnancy?

During pregnancy, your body starts preparing for breastfeeding even if you aren't sure yet if you will nurse and pump for your baby. Hormones like estrogen, progesterone, and prolactin increase blood flow and stimulate the growth of milk ducts and glandular tissue. Your breasts are building the systems needed to breastfeed your baby. This means more breast tissue and expanding milk ducts, which equal fuller, heavier and more sensitive breasts.

First Trimester Breast Changes (Weeks 1–13)

What’s happening?

If you are currently in your first trimester, around weeks 4-6 you will start noticing soreness or tenderness, tingling and sensitivity, and a fullness that suddenly makes your bra feel too tight. 

This stage can feel intense. Even light touch or putting on your current bra may feel uncomfortable. For some moms, these quick breast changes may mean going up one cup size right away in your breast tissue. As a first step, we highly recommend changing over to softer and more comfortable maternity bras that will allow for growth and expansion of your breast tissue. The biggest mistake I see moms make is waiting too long to switch into softer, stretchier bras. Your body is changing quickly, and compression from a pre pregnancy bra being too tight can cause unnecessary discomfort. During the first trimester, comfort should be top priority. 

Pro Tip - Your pregnancy bra size today won’t be your size in two months. Look for maternity bras with:

• Soft comfortable fabrics and elastics
• Flexible bra sizing (example: Small, Medium, Large, XL)
• No underwires, always choose wire free!
  
• Room for your breast tissue to grow

Second Trimester Breast Changes (Weeks 14–27)

What’s happening?

For some moms, the second trimester is when breast growth really becomes noticeable. Your breasts may increase another cup size and start to feel even heavier and more full. At this stage, the nipples may begin to darken and prepare for your baby to latch after birth. If you aren't used to having large breast tissue, it's common to feel like all of this is a big change. Keep in mind, this is your body's preparation for you to be able to breastfeed if you choose to! 

The second big change that will start to take place around 14 weeks is your ribcage starting to expand to make room for your growing baby. When it comes to maternity bras, this is why it's important to start shopping and select a comfortable maternity bra with extra support. So what does this mean? The 2nd trimester is where I recommend (if you haven't already) investing in high quality maternity and nursing bras you can start wearing now during your pregnancy. This is especially important if you have experienced that heavy feeling in your breast tissue and you need the additional support in the cup + additional room in the bra band. The right maternity bra support can completely change how your body feels during pregnancy.

Third Trimester Breast Changes (Weeks 28–Birth)

What’s happening?

By the third trimester, your breasts are in full preparation mode for breastfeeding. It's almost go time! At this stage, you may start to experience increased nipple sensitivity, more pronounced veins and itchy skin from the skin stretching and expanding. If you haven't already, it's extremely common in the 3rd trimester to start leaking colostrum, the baby's first form of milk. Don't be alarmed if you do, it's perfectly normal to leak during pregnancy!

Now that your breast tissue is prepared for birth, you will want to be prepared for additional changes when your breast milk comes in. After delivery, colostrum will change over to mature breastmilk typically around 2–5 days postpartum, which can create another dramatic size change to your breast tissue. For many moms, this engorgement may be the biggest size change they have experienced yet. We typically see each breast growing 1 additional cup size after birth. This now means your breasts are anywhere from 1-3 cup sizes fuller than your pre pregnancy size. For first time moms, this may sound terrifying but that's why I am here to help as a maternity bra expert.

How to know what size maternity and nursing bra I will need after birth?

By the time your baby has arrived, it's extremely important to tuck away your pre pregnancy bras and convert to maternity and nursing bras designed specifically for this. Your sizing is changing by the day (even by the hour) and cup specific pre pregnancy bras will be too rigid to offer enough flexibility for your breasts during this phase of life. Having bras designed for fluctuation instead of fixed sizing makes a huge difference in breast health and comfort.

SIZING: Your breasts may be larger than you think. It's not as simple as saying, "I'll just go up one bra size". To select the right size maternity and nursing bra for yourself, I always suggest measuring to see what your current sizing is, NOT basing it off of your pre-pregnancy bra.

Start by measuring your fullest part of your chest all the way around and then under your chest where the band sits, all the way around. Knowing these 2 measurements will be super important so you can review any bra size chart and see where you fit best. If you aren't sure what this sizing means, that's ok and I can help. You can review sizing questions with me directly to get fitted for a Davin & Adley Maternity and Nursing bra. To book your free size consult, schedule now!

Pro Tip - You don't need to purchase separate maternity bras and nursing bras. Several combo maternity, nursing and pumping bras exist so you can have an all in one bra for all stages of pregnancy and postpartum. 

Are Breast Changes During Pregnancy Permanent?

This is one of the most searched questions by first-time moms and the honest answer is: every mom is different. If you decide to breastfeed, breast tissue takes a minimum of 6-12 weeks to regulate post birth, so you may see the initial engorgement reducing after that time. Some women will stay very full in their breast tissue the entire time they are breastfeeding and others may start to reduce in size over the course of 12 months or longer.

After weaning from breastfeeding, you may return close to your pre-pregnancy breast size. It's common to notice changes in breast shape more than to your breast size. What actually impacts breast change the most are hormonal shifts, weight changes and skin elasticity. Hopefully genetics are in your favor! 

If you choose not to breastfeed, we still recommend wearing your maternity bra for the first few weeks after birth. Your postpartum hormones will still cause your breast tissue to swell and it may take up to 2 weeks or more for your breast soreness and swelling to reduce back to normal. A comfortable wire free bralette or cami is the best option for post birth comfort that can be worn for all of your postpartum recovery. If you are looking for a comfortable maternity bra without nursing clips, the Davin & Adley Amelia Cami is our favorite one! 

When Should I Buy Pregnancy or Nursing Bras?

From my decade of experience working with pregnant and postpartum moms, I can confidently say you will need new bras much earlier than expected. If your bra band is leaving painful red marks, your cup is overflowing, straps digging in and you feel like ripping your bra off at the end of the day, these are all signs it is time to upgrade!

If you have continued to read this entire post, make sure you remember this one thing... Please do NOT wait until after birth to pick out a new bra!