The present invention relates to a breast pump (10) for extracting milk (30) from a human breast comprising: a first breast receiving funnel (16) for receiving a first breast (28) of a user a vacuum pump (20) for generating an underpressure within the first breast receiving funnel (16) and a control unit (22) for controlling the vacuum pump (20) wherein the control unit (22) is configured to operate the vacuum pump (20) in at least two different modes an attachment mode (48) and a milk extraction mode (50) wherein in the attachment mode (48) the control unit (22) is configured to control the vacuum pump (20) to generate a constant underpressure within the first breast receiving funnel (16) allowing the user to attach the first breast receiving funnel (16) to the first breast (28) and wherein in the milk extraction mode (50) the control unit (22) is configured to control the vacuum pump (20) to generate a time variable underpressure profile within the first breast receiving funnel (16) for extracting milk (30) from the first breast (28).