Inclusion Criteria:  - healthy women (aged 20-35 years), at first trimester of pregnancy, of at risk for atopy baby  Exclusion Criteria:  concomitant presence of infections; concomitant presence of malignancies; concomitant presence of major gastrointestinal malformations; concomitant presence of immunodeficiencies; concomitant presence of autoimmune diseases; concomitant presence of chronic inflammatory bowel diseases; concomitant presence of functional gastrointestinal disorders; concomitant presence of celiac disease; history of abdominal surgery with gastrointestinal resection; concomitant presence of neuropsychiatric disorders; concomitant presence of central nervous system disorders; vegan diet; twin pregnancy; concomitant presence of genetic disorders; concomitant presence of metabolic disorders.