During pregnancy your abdomen and lower rib cage will increase in size to allow for the growth of your baby. This will cause the band measurement (right underneath your breasts) to increase during pregnancy, from the first trimester onwards.


Your breasts start changing in preparation for feeding a baby early after conception. Women often find their breasts are tender, and this may be your first indication that you are pregnant. Your breasts are likely to increase about one cup size during the first trimester.

So it’s really important that you understand how your body will change during pregnancy and that your pre-pregnancy bras will not fit you as your body starts to grow.


Bra fitting in the first trimester

Firstly, take a measurement under your bust, making sure the tape measure is firm against your rib cage.  This will give you your band size. If the number is an odd number, round up to the next even number.

Secondly, take a measurement around the fullest part of your bust, again making sure the tape measure is firm around your body.  The difference between your band size measurement and this measurement will give you the cup size.

For example, if your under bust measurement is 32 and your bust measurement is 37, you have 5 inches difference between those two measurements, so I’d suggest that you are around a 32DD in size.

Cup Size Difference in inches
A 1
B 2
C 3
D 4
DD 5
E 6
F 7
FF 8
G 9
GG 10

However, you then need to make some adjustments to that sizing:

  1. Ensure your maternity bra is fitted firmly on its tightest fitting so that there are hooks for you to expand the bra as your rib cage increases in size. This usually means that you should increase your band size by one measurement (i.e. increase from a 32 to a 34 band).
    Bra fitting on tightest hooks
    Bra fitting on tightest hooks
  2. If you increase your band measurement by one size, then you should decrease your cup size by one to keep the cup size the same in both band sizes (i.e. 32DD becomes 34D). If you keep the cup size the same in both band sizes, then the cup size will also be bigger in the larger band size.
  3. Ensure your breasts are fully covered by the bra cup to support your growing and changing breasts. A deep centre on the front of the bra is a good guide to ensure a fuller cup. Even if this is a style that you’re not used to you, may find it more comfortable with heavier breasts.
  4. Ensure the fabric is not pressing on any breast tissue. Check the top of your breast and under your arm especially.
  5. Choose a soft-cup bra rather than one with a wire – with your body and breasts constantly changing, a wired bra may fit well when bought, but may not fit in a couple of weeks time!
  6. Get re-fitted/checked regularly during your pregnancy to ensure the bra is supporting your breasts, especially if you choose to wear an underwired bra or if you feel uncomfortable in the bra you’re currently wearing.
  7. If there is a large difference in breast size between left and right, fit the larger breast and use a soft filler in the smaller cup to even up the look. Differences in breast size are often accentuated during pregnancy.

Bras for pregnancy

So now you have got your measurements, which bras should you choose? Do you want something soft and stretchy, or more structured?

Anita Maternity Bustier Bra
Anita Maternity Bustier Bra

The Anita Maternity Bustier is great for around the house or as a sleep bra and matches with the Anita Over the Bump Maternity Briefs which will grow with you through your pregnancy.

Of if you are larger in the cup, then the Sugar Candy Everyday Bra gives perfect support for those over an F cup.

Cake Sugar Candy Everyday Bra
Cake Sugar Candy Everyday Bra

If you prefer to have a more structured bra, then you can choose from a range of soft cup maternity bras which will give you the support you need.

Of course, there is no reason why you can’t wear a nursing bra through your pregnancy either and many nursing bras are designed with several sets of hooks to allow the bra to grow with you through pregnancy.

If you need any advice about measuring yourself for bra fitting for pregnancy or on the size or style of bras you should choose, then please get in touch and I’ll help you find the right bras for you.  I’m here to support you…through pregnancy & beyond!

Happy Shopping!

Emma x

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