Over the course of a woman’s life, her body will undergo a multitude of changes. There’s puberty, the fluctuations that come along with your cycle, and countless other reasons your shape may change, but you know which stage of life takes the cake for the most dramatic changes during the shortest period of time? You guessed it, pregnancy.

Over the course of your pregnancy and breastfeeding journey, the average number of times your bra size will change is 5! To ensure optimal breast health during this crazy time, a properly fitting maternity bra is essential. So let’s take out the guesswork and break down each stage of pregnancy, and which styles you should be wearing, and when.

Tutti Frutti Nursing Bra by Cake Maternity

The First Trimester

If you’re pregnant or have been in the past, you know how dramatic the initial breast changes can be. In fact, some women know they’re pregnant even before they take a test, just because of how their breasts are feeling!

During the first trimester, you can expect your breasts to increase in size, resulting in them being sensitive and tender, particularly when any bounce occurs. Your first instinct may be to wear your most supportive underwire bra to reduce the bounce factor, but this is the worst thing you could do! The sudden increase in size will most likely mean your pre-pregnancy bras already don’t fit, so if you wear a bra that’s too small for you, the wires can push into your breast tissue and the top edge of the cup may cut into your breast.

During this time your milk ducts will also be slowly gearing up in preparation for breastfeeding, so it’s imperative to wear a well-fitting, seamless bra that moves with you and reduces the risk of any damage to your precious ducts. These bras are engineered to grow with you, whilst offering the perfect amount of support.

Croissant Nursing Bra by Cake Maternity

The Second & Third Trimesters
So you’ve made it out the other side of the first trimester (congrats mama!), you can now expect your breast growth to settle down a bit. It will still incrementally increase, but the majority of the growth will be in your band size, rather than your cup size, as your rib cage expands.


During this time you can go back to wearing wired styles, but make sure you stick to flexi-wire rather than the rigid ones you were wearing pre-pregnancy. A few other things to look out for in a good maternity bra is stretch in the top of the cup to allow for further expansion, extra support in the lower cup like a platform sling, wide straps that don’t dig into your shoulders and a back band with extra hooks and eyes to allow for rib cage expansion. If you do opt for a flexi-wire style, look for ones that move and flex with you, that also have a wider smile line. This ensures it sits wider on your rib cage, meaning no pressure anywhere near your milk ducts.

Fun fact: Did you know that your cup size at 8 months pregnant is usually around the size it will be at 6 weeks postpartum when your milk supply has regulated?

With this in mind, you can purchase your nursing bras ahead of time, because chances are you’ll be a bit preoccupied once bub comes along! Just keep in mind that your band size will be significantly smaller postpartum, so fit it to the loosest hooks. Then when you’re breastfeeding, you can wear it on the tighter hooks because what was making your rib cage larger is now in your loving arms.

The Last Month of Pregnancy

Everything is swollen, your shoes don’t fit, your lungs are squashed, and you can’t eat a full meal because your stomach is being pressed between your ribs and your baby’s bottom. Now’s the time for a super comfortable bra, seeing as the simplest tasks such as brushing your teeth can be uncomfortable. So whip out those seamless bras and keep them on rotation.

Immediately Post-Birth

Brace yourself for some rapid changes, mama. Your breasts will significantly increase in size because their number one job is now feeding your baby. It will take around 6 weeks for your milk supply to regulate, so expect an increase of a few cup sizes during this time. Stick to your seamless bras and you and your breasts will be just fine.

Cake Maternity has expertly crafted and engineered bras designed specifically for each stage of pregnancy. Each style uses the highest quality fabrics for durability, comfort and support. So you can spend less time bra shopping, and more time focussing on the important things in life.

Katie is the proud mum of two beautiful girls and has been responsible for all the designs, style and fit at Cake Maternity for over a decade now. 

Katie is a nursing bra specialist and a fit, pattern and grading technician. She is passionate about breastfeeding and the many benefits it offers to both mum, bub and the environment. 

She is determined to make the breastfeeding journey a comfortable, supportive and beautiful one for all mums, understanding that it doesn’t always come easy to everyone. That’s why she has made it her mission to empower women as they mindfully navigate the world of motherhood and help make breastfeeding easier, through experience-driven innovation.

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