If you're breastfeeding, breast pumps allow you to pump milk so that someone else can feed your baby. This is important if you need to leave your baby for a significant amount of time (for example, if you're working). Breast pumps also come in handy when your breasts get engorged and baby is too sleepy to eat. With a breast pump, you can pump some of the milk out and save it for when baby is ready to eat.