To distinguish women's sizes from unisex clothing, women's sizes are labeled as fashion numbers: 36, 38, 40, 42, 44, 46.

women's clothing size chart .

The unisex and women's size charts differ not only in hips, chest and waist proportions. 
If you look carefully at the different dimensions, you will notice that the height in larger women's sizes is lower than in the corresponding unisex chart. In small sizes the difference between the charts is less noticeable. However, the contrast becomes much more significant in larger sizes. 
It is worth to take time and accurately measure yourself in order to find the right size. Kwark's clothes last many years so it is important that they are well-fitted. Good fit is crucial in case of the Power Stretch clothes, especially if you want to take full advantage of the fabric properties.