The aim of present study was to evaluate the level of I-FABP and the level of IgA and IgG to beta-lactoglobulin in mothers and their children in the Gestational Diabetes Mellitus (GDM) pregnancy cohort recruited from the Woman’s Clinic of Tartu University Hospital taking in consideration their BMI, level of IgA/IgG to B. adolescentis (strains DSM20083 and DSM20086) and B. breve (strain DSM20213). Here, FABP2 is linked to gestational diabetes.