The microbial population of the human gut (the gut microbiome) is an integral cog in the bidirectional communication axis that exists between the gastrointestinal tract and the central nervous system. African American infants disproportionately experience multiple, overlapping vulnerabilities such as preterm birth and formula rather than breast feeding that may disrupt the development of the infant microbiome. | Protocol for the Emory University African American maternal stress and infant gut microbiome cohort study