A hand-held breast pump comprises a body 7 having a breast-receiving portion 23 and a thread 24 for attaching a milk bottle 5, a diaphragm 25 including an actuating element (64), and a motor unit 1 including a motor 54 and a drive mechanism 62, the drive mechanism being configured to connect to the actuating element on contact (Fig. 6), in order to reciprocally drive the diaphragm and effect pumping. Also disclosed is a manual unit 4, which may be used in place of the motor unit.