The present application discloses novel hot-melt adhesive formulations, with excellent processability, even in processes at high line-speed and at a relatively low temperature, the formulations suitable for strongly bonding substrates that have openings, holes, voids or pores, both macroscopic and microscopic ones, like perforated plastic films, both with bidimensional or tridimensional structure; fibrous substrates, both woven and non-woven; porous plastic films, and the like, all mentioned substrates being widely used for the manufacturing of absorbent hygienic articles. The hot-melt formulations include, as their main or even unique constituent, at least one polymer composition formed by two polyolefins, substantially non-stereospecific, as showed by the low value of their crystallization enthalpy at time zero, the polyolefins having average Number Molecular Weights Mn that do not differ for more than about 6,000 g/mole, being the single average Number Molecular Weights of said polyolefins ranging from about 3,000 g/mole and about 30,000 g/mole.