A method to produce an absorbent article using a blank, includes the following steps: folding the side-edge portions of the side parts of either the rear portion or front portion in towards the inner cover sheet over supports placed on the side parts of this portion and extending along the full length of this portion, folding the blank about a transverse line in the crotch portion so that the end edges of the front portion and rear portion come to lie edge-to-edge and so that the side-edge portions of the folded-in portion overlap the folded-in side-edge portions of the second portion; and welding together the overlapping side-edge portions of the side parts within the area of the supports by way of ultrasonic or thermal welding.