Bacterial community structure associated with elective cesarean section versus vaginal delivery in Chinese newborns.

Objectives: Increasing attention is being paid to the potential for cesarean birth to influence the taxa of the bacteria that compose the infant intestinal microbiota. The present study characterized the diversity of the intestinal microbiota in newborn infants delivered vaginally (VD) or by cesarean section (CD). Methods: A cross-sectional study was performed using fecal specimens collected on days 2 and 4 of postnatal life from 25 VD infants and 16 CD infants. Profiles of the fecal microbiota were analyzed using polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis in combination with 16S ribosomal RNA (rRNA) gene sequencing of the clones corresponding to the degenerating gradient gel electrophoresis (DGGE) bands. Results: On days 2 and 4 of postnatal life, VD and CD infants did not differ in the richness and evenness of the fecal bacterial community; however, the taxa of the fecal microbiota were significantly different between the 2 groups. In VD infants, Escherichia coli, Bacteroides sp, and Bifidobacterium longum were the dominant microbes. In CD infants, Staphylococcus sp, Clostridium sp, Enterobacter sp, and Streptococcus sp were more common. Conclusions: These results demonstrate that delivery method has a profound influence on the structure of the intestinal microbiota in Chinese newborn infants. This is in accordance with data reported in other regions.