Effect of maternal exposure to antibiotics during pregnancy on the neonatal intestinal microbiome and health.

Antibiotics are widely used during pregnancy. Recent epidemiological studies suggest that maternal exposure to antibiotics during pregnancy is associated with increased risks of various diseases in offspring; host-microbiome interactions are considered to be involved in pathogenesis, as antibiotic-induced perturbations (dysbiosis) of the maternal microbiome can be transmitted to offspring. We reviewed the current status of antibiotic usage during pregnancy, transmission of maternal antibiotic-induced dysbiosis to offspring, and several diseases in offspring reported to be associated with maternal antibiotic exposure. Antibiotics must be properly used when necessary. While the adverse effect of maternal antibiotic exposure during pregnancy on the health of offspring has been demonstrated by several studies, more robust clinical evidence is necessary to define the best practice for antibiotic use during pregnancy. Epidemiologic studies have limitations in establishing causal links beyond associations; animal studies provide benefits in examining these links, however, microbiomes, gestation courses, and aging vary between host species. Understanding the underlying mechanisms of epidemiologic findings as well as the healthy microbiome during pregnancy and early life in humans would contribute to developing future microbial interventions for restoring antibiotic-induced dysbiosis during pregnancy.