Effects of IAP-EOGBSD on Offspring's Gut Microbiome and Immunity.

Inclusion Criteria: * Infants:37-41 weeks of age, born through vaginal delivery, 2500g\<= birth weight \< 4000g,0-3 years of age; * The mother: birth ranging in age from 18 to 40 years old, the single pregnancy, pregnancy 35 -41 weeks to complete the GBS screening; * The guardian agrees to participate in the study voluntarily. Exclusion Criteria: * Infants and children with serious congenital abnormalities, infections or clinical diseases; * Antibiotics should be used in infants within 2 weeks, probiotics, prebiotics and biostime should be supplemented, or long-term drug treatment should be given for digestive, immune, blood and other diseases; * Infant mothers: childbirth after long-term drug treatment due to digestive, immune, blood and chronic diseases during pregnancy; Or infants who were breastfed within 12 hours of antibiotic use after delivery; * Any medical or non-medical condition that the investigator deems inappropriate to participate in.