The use of a probiotic strain of Lactobacillus rhamnosus and a mixture of oligosaccharides, which comprises a percentage of 5-70%, by weight, of at least one N-acetylated oligosaccharide selected from the group consisting of GalNAcαβ1, 4Glc and Galß1, 5 6GalNAcαlß1, 4Glc, a percentage of 20-90%, by weight, of at least one neutral oligosaccharide, selected from the group consisting of Galß1, 6Gal, Galß1, 6Galß1, 4Glc, Galß1, 6Galß1, 6Glc, Galß1, 3Galß1, 3Glc, Galß1, 3Galß1, 4Glc, Galß1, 6Galß1, 6Galß1, 4Glc, Galß1, 6Galß1, 3Galß1, 4Glc, Galß1, 3Galß1, 6Galß1, 4Glc and Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß1, 3Galß, 4% 50%, by weight, of at least one sialylated oligosaccharide, selected from the group consisting of NeuAcαß1, 4Glc and NeuAcαß1, 4Glc, in the manufacture of a medicament or therapeutic nutritional composition, to reduce the risk of development subsequent allergy, in young children lac tantes or babies, who were born through a caesarean section.El uso de un cepa probiótica de Lactobacillus rhamnosus y una mezcla de oligosacáridos, la cual comprende un porcentaje del 5 - 70 %, en peso, de por lo menos un oligosacárido N-acetilado seleccionado de entre el grupo consistente en los GalNAcαß1, 4Glc y Galß1, 5 6GalNAcαlß1, 4Glc, un porcentaje del 20 - 90 %, en peso, de por lo menos un oligosacárido neutro, seleccionado de entre el grupo consistente en los Galß1, 6Gal, Galß1, 6Galß1, 4Glc, Galß1, 6Galß1, 6Glc, Galß1, 3Galß1, 3Glc, Galß1, 3Galß1, 4Glc, Galß1, 6Galß1, 6Galß1, 4Glc, Galß1, 6Galß1, 3Galß1, 4Glc, Galß1, 3Galß1, 6Galß1, 4Glc y Galß1, 3Galß1, 3Galß1, 4Glc, y un porcentaje del 5 - 50 %, en peso, de por lo menos un oligosacárido sialilado, seleccionado de entre el grupo consistente en los NeuAcαß1, 4Glc y NeuAcαß1, 4Glc, en la fabricación de un medicamento o de una composición nutritiva terap