sizeinfo underwear


During pregnancy, your figure is constantly changing. Bust and hip measurement changes can already be noticed within the first two months of pregnancy. We took these natural body changes into consideration during the development of our cuts and materials.

You can use your normal (pre-pregnancy) size as a basis for your order.

If you have any doubts, our customer service will be glad to assist you.


Bra fitting guide - how to find the right size

1. Find your BAND SIZE

The importance of choosing a well-fitting maternity and nursing bra:
Wearing your normal bra, place the tape measure around the rib cage just underneath your bust, making sure the tape measure is flat and straight across your back. Pull the tape really tight and measure in cm. Use the chart below to find your band size:

Chart for bras

Band size
cm Band size
74 - 78 75
79 - 83 80
84 - 88 85

2. Find your CUP SIZE

Now measure across the fullest part of the bust – this is roughly at nipple height. The tape should be quite loose (again, you should be wearing your existing bra). Find your band size in the top row, then go down the column to find your cup size. For example, if your band size is 80, and your cup measurement is 95cm, your correct bra size is 80C.

Chart for bras: cup size in cm
Cup size
B Cup
86-88 91-93 97-98
C Cup
89-90 94-96 99-101
D Cup
91-93 97-98 102-103
E Cup 94-96 99-101 104-106
F Cup 97-98 102-103 107-108

3. Fit the bra – on which hook?

You should fit a maternity bra on the tightest hook so that it can be let out as your ribcage expands outwards.

If you are buying a nursing bra, you should fit it on the 4th hook. As your ribcage falls back to its natural place in the weeks and months after your baby is born, you can tighten the bra. This will also allow the bra to be tightened.

You should also be able to fit your hand inside the nursing bra cup so that you have enough space for breast pads.


4. What about bottoms, nightwear or swimwear sizes?

How do our S, M, L, XL compare to normal EUR sizes? Our sizes are the same as non-maternity clothes, but we cut them to fit a growing bump.

  • Small is equivalent to a EUR 36
  • Medium is a EUR 38
  • Large is a EUR 40
  • X-large is a EUR 42



Do you need help choosing the right size? Do you have questions regarding the collection? Or do you need to know anything regarding your order?

Simply phone us in the bellybutton Customer Service Centre from Monday to Friday 10 a.m. up to 6 p.m.:

International Hotline: + 49 (0) 180 5 88 55 81 (Providers charges may vary.)

We will answer all questions surrounding our product range and will be pleased to help you.