Providing breast milk is one of the best things you can do for your baby’s health and development. Pumping your milk is one way to provide breast milk to your baby. However, germs can grow quickly in breast milk or breast milk residue that remains on pump parts. Providing breast milk is one of the best things you can do for your baby’s health and development. Pumping your milk is one way to provide breast milk to your baby. However, germs can grow quickly in breast milk or breast milk residue that remains on pump parts