MOdification Of THe Early-Life Respiratory Microbiome Through Vaginal SEEDing

Eligible children will be randomized 1:1 to have their nose swabbed with either maternal vaginal secretions or a sterile swab (intervention vs. control group, respectively). The procedure will be performed following birth by C-section and immediately after the initial newborn care by the general pediatric team. The mother and child will then receive usual medical care as determined by their health care providers. Follow-up will occur at multiple time points during the child's first 6 months of life. One planned interim analysis to assess the safety of the procedure will be conducted. The intervention aims to transfer the maternal vaginal microbiome to the nasal cavity of cesarean-born children at birth (i.e., vaginal seeding of the URT). Hence, the intervention simply attempts to replicate the natural exposure to maternal vaginal secretions during vaginal delivery in children born by C-section.