Preterm Birth Is Correlated With Increased Oral Originated Microbiome in the Gut

Abstract

BackgroundPreterm birth is one of the leading causes of perinatal morbidity and mortality. Gut microbiome dysbiosis is closely related to adverse pregnancy outcomes. However, the role of the gut microbiome in the pathogenesis of preterm birth remains poorly studied.MethodWe collected fecal samples from 41 women (cases presenting with threatened preterm labor =19, 11 of which delivered preterm; gestational age-matched no-labor controls, all of which delivered at term = 22) were recruited for the study. We performed 16S rRNA amplicon sequencing to compare the composition of the gut microbiome in threatened preterm labor cases and controls and among women who delivered preterm and at term. By annotating taxonomic biomarkers with the Human Oral Microbiome Database, we observed an increased abundance of potential oral-to-gut bacteria in preterm patients.ResultsPatients with preterm birth showed a distinct gut microbiome dysbiosis compared with those who delivered at term. Opportunistic pathogens, particularly Porphyromonas, Streptococcus, Fusobacterium, and Veillonella, were enriched, whereas Coprococcus and Gemmiger were markedly depleted in the preterm group. Most of the enriched bacteria were annotated oral bacteria using the Human Oral Microbiome Database. These potential oral-to-gut bacteria were correlated with clinical parameters that reflected maternal and fetal status.ConclusionsThis study suggests that patients who deliver preterm demonstrate altered gut microbiome that may contain higher common oral bacteria.

Causal associations between gut microbiota and adverse pregnancy outcomes: A two-sample Mendelian randomization study

“…Another case-control study showed that pregnant women with pre-eclampsia (PE) had a high abundance of Fusobacterium and Veillonella and a relatively low abundance of Faecalibacterium and Akkermansia compared with normotensive pregnant women (Chen C. et al, 2020;Chen X. et al, 2020). Yin et al (2021) reported that women with preterm birth (PTB) showed a distinct gut microbiome dysbiosis compared with those who delivered at term. Opportunistic pathogens, particularly Porphyromonas, Streptococcus, Fusobacterium, and Veillonella, were enriched, while Coprococcus and Gemmiger were markedly depleted in the preterm group (Yin et al, 2021).…”

“…Yin et al (2021) reported that women with preterm birth (PTB) showed a distinct gut microbiome dysbiosis compared with those who delivered at term. Opportunistic pathogens, particularly Porphyromonas, Streptococcus, Fusobacterium, and Veillonella, were enriched, while Coprococcus and Gemmiger were markedly depleted in the preterm group (Yin et al, 2021). However, whether these associations are causal has not been established because of potential biases including residual confounding factors and reverse causality.…”

Microbiota of preterm infant develops over time along with the first teeth eruption

“…The general uptrend of Veillonella spp. abundance was shown in several studies in healthy and preterm infants ( Dzidic et al, 2018 ; Yin et al, 2021 ; Xu et al, 2022 ). In this study, the relative abundance of V. dispar also increased while growing up in both groups; however, V. atypica did not show this trend, which was stable in the healthy controls from CT0 to CT1 stage and decreased markedly in the preterm infants along with two lower primary central incisors teeth eruption.…”

Preterm Labor, a Syndrome Attributed to the Combination of External and Internal Factors

“…138,139 The previous microbiome reported in placenta seemed to be of more possibility of contamination from sampling or procedure of sample processing. 140,141 Besides the microbiome in genital tract, a decrease in a-diversity of microbiome, 142 and increased oral originated bacteria 92 in the gut were both correlated with sPTL.…”