Impact Of Delivery Mode On Infant Gut Microbiota During The First Year Of Life

Objective1.To analyze the infant gut microbiota composition and alterations during the first year of life,as well as the changes in the diversity and composition of infant gut microbiota over time.2.To explore the effects of delivery mode on infant gut microbiota,and may provide a solid foundation for future study on the characteristics and influencing factors of infant gut microbiota.MethodsThis study included 45 infants.According to mode of delivery they were respectively divided into two groups,27 cases in vaginal delivery group and 18 cases in cesarean delivery group.Fecal samples were collected at 1 day and 3,6,12 months postpartum,and were stored at-80℃.The researcher collected information on infant feeding mode,body length and weight,and medication(antibiotics and probiotic preparations).Fecal samples at 1 day and 3,6,12 months after birth were analyzed by high-throughput sequencing.Results1.In fecal samples of infants at 1 day,the relative abundance of Escherichia-Shigella(10.26%vs 25.22%)and Parabacteroides(0.06%vs 4.44%)was decreased,while the relative abundance of Klebsiella(37.86%vs 15.14%),Enterobacter(2.52%vs 0.80%),Salmonella(2.02%vs 0.88%),Enterobacteriaceae(unclassified,1.83%vs 0.77%)and Dialister(1.39%vs 0.50%)increased in cesarean section delivery group compared with vaginal delivery group(P<0.05).2.In fecal samples of infants at 3 months,the relative abundance of Pelagibacterium(0.44%vs 0%),Aliihoeflea(0.34%vs 0%)and Xanthomonadaceae(uncultured,0.21%vs 0%)was increased in cesarean section delivery group compared with vaginal delivery group(P<0.05).3.In fecal samples of infants at 6 months,the relative abundance of Rothia(0.69%vs 1.91%)was decreased,while the relative abundance of Lachnospiraceae incertae sedis(5.01%vs 0.03%),Enterococcus(1.21%vs 0.40%)and Peptostreptococcaceae incertae sedis(1.10%vs 0.01%)increased in cesarean section delivery group compared with vaginal delivery group(P<0.05).4.In fecal samples of infants at 12 months,the relative abundance of Halomonas(0%vs 0.38%)and Lachnospiraceae(uncultured,0.16%vs 0.17%)was decreased,while the relative abundance of Blautia(2.69%vs 0.25%),Anaerostipes(2.22%vs 0.25%),Ruminococcaceae(uncultured,1.94%vs 0.42%),Dorea(1.01%vs 0.02%)and Ruminococcaceae incertae sedis(0.62%vs 0.10%)increased in cesarean section delivery group compared with vaginal delivery group(P<0.05).ConclusionDelivery mode is an important factor affecting the distribution characteristics of infant gut microbiota.Our results confirm that the fecal microbiota composition differs between cesarean section delivery group and vaginal delivery group at different time points after birth.And our results also confirm that gut microbial composition and alterations at the phylum and genus levels between two groups.