Abstract: A method of manufacturing a thin plate or band from copper or a copper alloy is disclosed, the plate or band having flow conduits parallel to its plane, in which a thicker copper plate billet, which also has flow conduits parallel to its plane and the total wall thickness of which, as measured in a direction perpendicular to the plane of the plate, is equal to the thickness of the plate on both sides of the flow conduit, is cold worked to its final material thickness, whereafter the flow conduit flattened during the rolling is opened by means of pressure produced inside it.

Abstract: A copper wire for intrauterine contraceptive devices is disclosed as having a core wire of a flexible tough metal nobler than copper and a copper coating fixed on the core wire by means of a thin diffusion layer.

Abstract: An intrauterine contraceptive device, resembling the shape of T, deviating from that, however, by having in the end of a vertical arm a loop which is easy to compress for insertion and having in the upper end of the vertical arm two arms departing to opposite sides and jointed smoothly to the vertical arm so that the bending radius is relatively big, the angle between the horizontal and vertical arm being preferably smaller than 90.degree..