Absorbent sanitary articles (2), such as nappies or incontinence pads with an elongated central body (2a) and at least one pair of closure tabs (5), are manufactured on a machine (1) by which the tabs (5) are directed in pairs from a feed unit (13) onto a transport line (6) carrying the articles (2) toward a sealing station. The feed unit (13) operates by making skew cross-cuts (16) in a continuous strip (15) of material, so as to generate a succession of tab elements (5) appearing trapezoidal in outline; the tab elements (5) are then distanced one from another in alternation along a direction (D3) transverse to their feed direction (D2) through the machine, so as to obtain two single columns (23) which are taken up by a roller (27) and aligned one with another so that the single tab elements (5) are ordered into a succession of transversely aligned pairs. The alignment roller (27) rotates tangentially to the transport line (6) and is timed to place one pair of tab elements (5) on each advancing article (2).