Poly(L-lactic acid) (200,000 in weight average molecular weight and 175° C in melting point) is melt-spun at 200° C and drawn to obtain a single filament having a diameter of 0.05 mm. Two lengths of the filament are twisted to prepare a filamentous substance, which is cut to a length of 7 cm to obtain a vasoocclusive article 1 in the form of a single line. The occlusive article is free of the problems conventionally experienced.
