The invention concerns a device for the atraumatic transfer of a material or substance with a reproductive, therapeutic or diagnostic purpose into a female mammal, comprising a body assembly, an outer sheath suitable for being inserted as far as the start of one of the uterine horns, an inner sheath inside the outer sheath and capable of being extended into the uterine horn, and a piston inserted into the inner sheath order to push the material or substance up to the distal end of the inner sheath. The body assembly comprises a rod extending away from the outer sheath, and on which a shuttle assembly is slidingly mounted, comprising a primary shuttle, mounted sliding on said rod and to which the piston is attached, and a secondary shuttle, mounted sliding on said primary shuttle and to which the inner sheath is attached.