Measure your chest (we know this seems odd, but it works!). Place the measuring tape around your back and under your armpits. Check in the mirror to ensure the measuring tape is parallel to the floor along your back as well as along your breasts. The measuring tape should be placed above your breast tissue. The tape should be snug around your body and make sure that you don’t have any fingers underneath the tape. If you are in between sizes, round up or down to the nearest even number. This will be your rib band size (34, 36 etc.).

Measure around the fullest part of your breasts, over your nipple area. This is a looser measurement than the rib band measurement. Hold the end of the measuring tape at the side of your breast. While holding both ends of the tape with one hand, use your free hand to press the measuring tape in between your breasts to your chest. This will provide a more accurate cup size measurement.

Subtract the rib band measurement from the cup size measurement. Each number or inch represents one letter. For example, if your rib band is 34 and your cup measurement is 38; 38-34 = 4, 4 equates to a D (2=B, 3=C, 4=D, 5=DD(E), 6=DDD(F)…). You are a D cup. Your nursing bra size is a 34D.

In your second trimester, your breasts continue to grow (thanks to increased blood flow and expanding milk glands), and you’ll most likely be craving more support than your regular bras can offer. Consider our Body Silk Seamless Nursing Bra that offers stretch and support to make your days that much more comfortable. This bra is guaranteed to become your favorite and take you right through your nursing journey.

Because your rib cage has expanded to accommodate your baby, your rib band could be one size larger than it will be after you deliver. Your cup size has increased one-to-two sizes from pre-pregnancy, and could go up one more size (really!) in the first days after your baby is born. Bottom line: buy nursing bras where the band fits comfortably on the loosest setting, so you can tighten it after your baby is born, and with stretchy cups that can handle the changes in breast size.

Your changing body has one big finale: your milk comes in during the first few days after giving birth. This can be when your breasts are at their largest, usually one cup size up from your third trimester. Other changes include a higher body temperature and tender nipples, so for breathability and comfort, opt for cotton bras with flexible cups. Most moms feel more comfortable sleeping with a bra at this stage so be prepared with a comfortable and well-fitting bra for sleep and every day. Bravado Design bras offer key features that are so important during these early days and throughout your breastfeeding journey, including full drop-away cups so that the baby has skin-to-skin contact and access to the breast, plus, an easy, one-handed clip.

After you and your baby get used to breastfeeding, your breasts will adjust too, going down one cup size from when you were nursing a newborn. You will likely tighten your bra band as your rib cage decreases in size. After breastfeeding has been established, around 6-8 weeks, you can choose whatever bra you prefer, including a professionally fitted underwire nursing bra. Remember that your bra should not be uncomfortable or tight—constriction can lead to plugged milk ducts and breast infections.