The present invention provides a breastshield for use in a breastpumping system for expressing milk, the breastshield being of such a construction that substantially limits the amount of air between the breast/nipple and the breastshield surrounding the breast/nipple, and most preferably virtually eliminates any air at least in the area of the breast and nipple. In some embodiments, any air in the breastpumping system is substantially eliminated. With the amount of air limited, the mechanism used for generating the pressure difference in the breastshield (e.g., vacuum or negative pressure), such as a diaphragm pump, does not need to do as much work. Less energy is required for the expression of milk, and thus the size of pump used can be decreased, thereby reducing the overall cost of the device.
