A breast pump for expressing human breast milk has a housing (8), a pumping chamber (47) with a driven pump membrane (7) for generating a vacuum, and also has a breastshield (2) with an interior (200) in which to position a breast. Expressed milk flows from the interior (200), through a milk channel, into the pumping chamber (47), which has an outlet opening (480) through which expressed milk flows from the pumping chamber (47) into a milk-collecting container (9). The breast pump has a multi-part hygiene module (2, 3, 4, 5) having a first part (2) with a throughflow opening (24, 25) for connection to the interior (200), having a valve body (3) with at least one valve (34, 37), and having a second part (4) with a rigid shell for forming the pumping chamber (47). The valve body (3) is arranged between the first and second parts (2, 4) and the hygiene module (2, 3, 4, 5) can be connected, as a whole, to the housing (8) of the breast pump in a sealing and releasable manner.
