The intestinal microbiome of preterm infants

Abstract Preterm birth causes a disruption in the developmental pattern for which the human is programmed. When prematurely separated from the mother during the last trimester of pregnancy, the fetus may be provided partial developmental continuity with appropriate support measures. As an integral component of this support, exposure to environmental microbes has been found to be critical. Evidence for in utero commensal colonization of the fetus remains controversial, but it is clear that maternal and newborn exposure to appropriate microbes stimulates developmental pathways for the neonate. Perturbations of normal microbiome exposures during pregnancy, parturition, and early infancy by stress, antibiotics, diet, and other environmental factors play major roles in interruption of the developing metabolism, nervous system, and immune system. This chapter focuses on the early interplay between the microbiome of the infant born preterm and how it can influence neurodevelopment and diseases of prematurity, including necrotizing enterocolitis, sepsis, and lung disease.