Your breasts might feel tender, larger or fuller often – but not always – around the second month of pregnancy. You may feel the need for a pregnancy or nursing bra with a larger cup size. For some women, breasts will continue to grow over the course of the pregnancy while others will only feel the difference in the latter stages of pregnancy.
As your baby grows, your rib cage also increases often by one or two sizes. This will be particularly noticeable for petite women or those carrying their baby high.
Most women will need a maternity bra one or two size above their normal size both in cup size and rib band size.
When your baby is born and you start breastfeeding, your baby will first receiving colostrum. After a few days, your milk ‘comes’ in. You may need a nursing bra with cup sizes one or two size larger from your third trimester.
After about six weeks, breastfeeding settles and your body and breast shape will settle down too. Most women will decrease a few cup sizes around that time. Your rib band size will start decreasing too to go back to your pre-pregnancy size.
This will be your breastfeeding bra size for the rest of your breastfeeding years. On average, it is about your pre-pregnancy rib band size and a cup size above.
Remember, all women are different and breastfeeding experiences vary. These are just guidelines.
Maternity and nursing bras are designed to adjust to these changes. You will not need to buy a new nursing bra every time your body or breast change. You will also be able to buy your breastfeeding bra to wear while pregnant.
Here are some examples to illustrate how your bra size will likely change: