Omics Sequencing of Specimen Derived From Mother-Infant-Pairs

Inclusion Criteria: * healthy pregnant women aged between 20y and 40y. * Vaginal birth * BMI\<23.5 before pregnancy * Infants' birth weight, between 2500g and 4000g. Exclusion Criteria: * gestational diabetes * diagnosis of depressive disorder during pregnancy * gestational hypertension * diagnosis of other diseases during pregnancy * Under probiotics or antibiotic treatment from 3 months prior to pregnancy till 3 months after delivery * histrory of smoking and drinking alcohol * history of diarrhea from 3 months prior to pregnancy till 3 months after delivery