We've designed our maternity clothes in line with your pre-pregnancy clothing size for extra ease, giving you one less thing to think about. Many pieces are infused with our signature ruching and wrapping for a flawless fit at every stage.
Please refer to the chart below for clarification. Simply, take your pre-pregnancy clothing size, and look across the chart to find your Isabella Oliver size.
So, if you were usually a UK 12 before you were pregnant, just order an Isabella Oliver size 3. Additionally, if you are a UK 14, then our size 4 is for you.
If you are in any doubt, please check against our measurement chart to find your correct size against your body measurements. Alternatively, you can also contact our customer services team.
Isabella Oliver Clothes Sizing Guide
0 | 1 | 2 | 3 | 4 | 5 | 6 | |
---|---|---|---|---|---|---|---|
UK size | 4-6 | 8 | 10 | 12 | 14 | 16-18 | 20 |
US size | 0-2 | 4 | 6 | 8 | 10 | 12-14 | 16 |
EU size | 32-34 | 36 | 38 | 40 | 42 | 44-46 | 48 |
AU/NZ size | 4-6 | 8 | 10 | 12 | 14 | 16-18 | 20 |
X-Small | Small | Medium | Large | X Large | |
---|---|---|---|---|---|
UK size | 6 | 8-10 | 12-14 | 16-18 | 20 |
US size | 2 | 4-6 | 8-10 | 12-14 | 16 |
EU size | 34 | 36-38 | 40-42 | 44-46 | 48 |
AU/NZ size | 6 | 8-10 | 12-14 | 16-18 | 20 |
Isabella Oliver Pre Pregnancy | Bust | Chest | Waist | Top Hip | Low Hip | Arm | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
cm | in | cm | in | cm | in | cm | in | cm | in | cm | in | |
0 | 81 | 32 | 78 | 30¾ | 65 | 25½ | 77 | 30¼ | 92 | 36¼ | 54.4 | 21½ |
1 | 83.5 | 33 | 80.5 | 31¾ | 67.5 | 26½ | 79.5 | 31¼ | 94.5 | 37¼ | 54.7 | 21½ |
2 | 86 | 34 | 83 | 32¾ | 70 | 27½ | 82 | 32¼ | 97 | 38¼ | 55 | 21½ |
3 | 91 | 35¾ | 88 | 34½ | 75 | 29½ | 87 | 34¼ | 102 | 40¼ | 55.6 | 21¾ |
4 | 96 | 37¾ | 93 | 36½ | 80 | 31½ | 92 | 36¼ | 107 | 42 | 56.2 | 22 |
5 | 101 | 39¾ | 98 | 38½ | 85 | 33½ | 97 | 38¼ | 112 | 44 | 56.8 | 22½ |
6 | 108 | 42½ | 105 | 41½ | 92 | 36¼ | 104 | 41 | 119 | 47 | 57.4 | 22½ |
* All measurements are based on our standard size 2/UK size 10, 160 -165cm, 5'4 - 5'6 customer.
Isabella Oliver Trousers Lengths
Isabella Oliver | cm | in |
---|---|---|
Regular | 81 | 32 |
Long | 86 | 34 |
Isabella Oliver Jeans Sizing Guide
1 | 2 | 3 | 4 | 5 | 6 | |
---|---|---|---|---|---|---|
UK Pre-pregnancy size | 8 | 10 | 12 | 14 | 16-18 | 20 |
Isabella Oliver Maternity sizing | 25 | 27 | 29 | 31 | 33 | 35 |
Expecting Twins?
If you are pregnant with twins, we recommend you go up a size. Therefore, if you were a UK size 12 (Isabella Oliver size 3) before you were pregnant, order an Isabella Oliver size 4.
Clothing measurements in centimeters and inches can be found on our individual product pages. If you require more information please contact us and we'll be delighted to help you.

Bust
Wearing a bra, place the tape around the fullest part of your bust, ensuring the tape is straight across the back.
Waist
This is the slimmest part of your natural waistline. Above the naval and below the ribcage.
Hip
Place the tape around the fullest part, usually over your bottom or at the top of your thighs.
Inside leg
The measurement between the top of your leg (at the crotch) to the ankle.
Footwear
UK Size | EU Size | US Size |
---|---|---|
3 | 36 | 5 |
4 | 37 | 6 |
5 | 38 | 7 |
6 | 39 | 8 |
7 | 40 | 9 |
8 | 41 | 10 |
Our collection is designed to make you feel fabulous throughout your pregnancy. Please contact us if you are in any way disappointed with our clothes or service, so we can make things right.