Buying well-made, well-fitting maternity bras is key to ensuring support and comfort for your breasts at a time when the tissue is at its most delicate. Follow our top tips below to find the right bra for you.

If you are looking for a nursing bra please read our article here – Nursing Bra Size and Buying Guide.

More 4 Mums offer a great selection of Affordable Maternity Bras.

seamless maternity nursing braWhy do I need a Maternity Bra?

You’ll probably start looking for a maternity bra 3 or so months into your pregnancy as you notice your breasts becoming more tender, growing in size and your rib cage expanding; your bra size might go up from 2 sizes larger to as much as 4 sizes. The increase in weight and size of the breast will also cause the skin to stretch and the breast to drop, which is why it is important to be fitted for a new bra regularly. A good fitting, specifically designed maternity bra can prevent and minimise stretch marks and discomfort, keep you cool and absorb any leaking fluid.

How Many Maternity Bras Do I Need?

You’ll probably need two maternity bras for washing however depending on how much your bust size changes you may need to increase the bra size later in pregnancy.

To work out your band size (the number part) take a tape measure and place it around your body so that it lies flat just under your bust. Take this measurement in inches, rounding up if the circumference comes out as an uneven number (i.e. if the actual measurement is 37″ your correct band size would be ’38’). You now have your band size.

To work out your cup size you should take the tape measure and place it around the widest part of your bust whilst wearing a well fitted, unpadded bra. Again, take this measurement in inches. You will then need to work out the difference between this measurement and your band size to find out your cup size. Every inch of difference between these two measurements is equivalent to an increase of one cup size.

e.g. Say your band size is 36 inches and your bust measurement is 39 inches, the difference between the two is 3 inches. Using the table below you can see that this is equivalent to a C cup size, so your overall bra size would be 36C.

Bust measurementCup Size
1″ – 2″A
2″ – 2 1/2″B
2 1/2″ – 3 1/2″C
3 1/2″ – 4 1/2″D
4 1/2″ – 5″E
5″ – 6″F
6″ – 7″G


Ensure the maternity bra is fitted firmly on its tightest fitting so that there is space to grow into as the rib cage expands.  Choose a soft-cup bra rather than one with a wire – with the body and breasts constantly changing, a wired bra may fit well when bought, but may not fit in a couple of weeks time.