An electric breast pump is disclosed as including a hood to be fitted over a breast of a user, a chamber in fluid communication with the hood member via a one-way valve, a pump motor operatively associated with a pump diaphragm movable to draw air from the hood into the chamber via the valve, in which the chamber has an opening and a lid which is operatively associated with the motor, in which the lid is movable between a first position to close the opening and a second position in which the opening is open, and in which the lid is at the first position when the motor is in operation and is at the second position when the motor is not in operation. The breast pump also includes sensors for detecting the passing of milk, and a microcontroller for calculating the rate of flow of milk on the basis of data received from the sensors.