It’s likely that your band size will decrease after delivery to closer to what you were pre-pregnancy. At the same time, your cup size will likely increase one to two cup sizes once your milk comes in. Your breasts will continue to fluctuate in size as they alternate between filling up with milk and breastfeeding. Our bras are alpha-sized bras (small, medium, large, etc.) that are designed to stretch to accommodate these fluctuations in your breasts.