A method and system for enhancing expression of milk from breast alveoli includes providing a pump that delivers a pulsed vacuum. The pulsed vacuum may be delivered by a vacuum pump employing a rigid piston that operates as a multi-stroke accumulator pump. In an embodiment, a piston head of the rigid piston undergoes a non-linear motion relative to a sidewall of a cylinder of the pump, resulting in an oscillatory impulse on the interior of the vacuum chamber in the cylinder. The vacuum pulse frequency of the pump is applied over a cyclical vacuum frequency that would otherwise be applied had the piston head only moved up and down while maintaining a perpendicular relationship to the sidewall of the cylinder.