To find your Band size:
Measure under your arms, high on the back, around the top of the chest. Enter this number in the Band field to the right:
To find your Cup Size:
Wear an unpadded bra, measure loosely around the fullest part of the bust. Enter this measurement in the Cup field to the right:
Click "Calculate" to find your size.
The Easy-Zip Nursing Bra may runa little larger than what you are used to. Studies show that breastfeeding mothers tend to go up one cup size from their pre-pregnancy size while keeping the same band size. Your size during the last 3 to 4 weeks of your pregnancy is often the size you will need when starting to breastfeed.
Cross-Over Cup Sizing
When measuring for a bra, it is helpful to know the cross-over cup sizing to help with your fitting. Use the chart below to "size up" while keeping the same cup size.
For example: If you fit well in the cups and front of a 36C, however you need more length around the band. You can "size up" to a 38B, keeping the same cup size but adding the needed length around the band. All bras along the diagonal paths(pink arrows) share the same sized cup.

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