The medical puncturing device includes a housing (12), a shield (13), and a skin puncturing assembly disposed within the housing. The shield is axially movable in the housing. The skin puncturing assembly includes a movable carrier and a skin puncturing element mounted to the carrier. A distal end of the skin puncturing element is adapted for puncturing the skin of a patient. The carrier is movable from a retracted position wherein the skin puncturing element is disposed within the shield to a puncturing position wherein the distal end of the skin puncturing element is exposed. The carrier is maintained in the retracted position by engagement of flexure members or a retaining tab with the carrier. A drive spring is provided to move the carrier from the retracted position to the puncturing position. A retraction spring is provided to return the carrier and skin puncturing element into the housing.