During pregnancy it is normal for breasts to go up a cup size (or two) and to put on weight across the hip, bum and thigh area.
Cherry Melon styles are specifically designed to accommodate for this growth. Therefore as a rule of thumb, we suggest that you stick to your pre-pregnancy size.
You can also use these measurements in cm's below to guide you. Start by taking the following two measurements, then find your size in the table below.
Bust: wearing a bra, measure around the fullest part of your bust
Hip: measure the widest part of your hips, including your bum
If you are still tempted to order one size up, we strongly suggest only doing so if (a) you have a very large bust (normal preggie growth excluded); (b) you feel like you have gained extra weight (above the normal weight gain range); (c) you're having twins.