Meconium Microbiota Composition and Association with Birth Delivery Mode

Abstract

Recently, the intrauterine sterile environment theory has been questioned. Growing evidence shows that microbial in utero pioneer gut colonization could occur prebirth, and this initial colonization may play an important role in the development of the neonate immune system and setting up a niche for the adult-like microbiota. In this study, we compared the microbiota networks from public available meconium datasets from different countries. The findings showed differences at the genera level and were country-dependent. We generated and analyzed bacterial networks, at the genera level of meconium samples from c-section and vaginally delivery modes. Interestingly, bacterial networks from the c-section-delivered meconium samples tended to have a bigger diameter but fewer correlations, whereas the vaginally delivered meconium networks were smaller and with a higher number of correlations. Even more, the networks were similar in the delivery mode, even between countries, at the genera level. The c-section networks suggest incomplete colonization or important lack of bacteria, promoting the susceptibility of the network to receive new members, beneficial or pathogens. These results suggest that the network analysis contributes to the knowledge of microbiota composition, identifying microbial associations, despite the differences between the environment and country habits, and obtaining a better understanding of microbial gut colonization.