An elastic film has a perforation formed by perforation holes that are elongated along a preferred expanding direction in the unexpanded state, wherein the ratio of the length of the perforation holes determined along the preferred expanding direction to a width of the perforation holes determined perpendicular thereto amounts to at least 3:2. The elongation at break along the preferred expanding direction is at least twice as high as the elongation at break determined perpendicular thereto along the width of the perforation holes.