BioProject

Intrauterine growth restriction (IUGR) is a common obstetrical complication that is associated with an increased risk of perinatal mortality and morbidity. More...

Intrauterine growth restriction (IUGR) is a common obstetrical complication that is associated with an increased risk of perinatal mortality and morbidity. IUGR is defined as a fetus that is unable to achieve its genetically determined potential size. This growth inhibition has many potential etiologies, including congenital infections, as well as uteroplacental insufficiency, a condition in which the fetus is pathologically small due to a placenta that not providing sufficient oxygen and nutrients. Although the human placenta is considered a sterile environment, recent microbiome studies reveal the presence of diverse commensal placenta microbiota, as well as pathogenic flora known to be associated with intrauterine infection. Therefore, in this pilot study, we tested whether IUGR is also associated with changes to the placental microbiota.We surveyed the placental microbiota from 20 IUGR and 20 AGA (appropriate for gestational age) pregnancies without known complications using bacterial 16S rRNA sequencing. R-package [Vegan] was used to compare the overall microbiota diversity, and the LEfSe method was utilized to elucidate differential taxa features associated with IUGR. Placenta microbiota screening demonstrated signals from a diverse range of flora including predominant phyla such as Proteobacteria, Fusobacteria, Firmicutes and Bacteroidetes. The overall microbiota dissimilarities (beta-diversity) were not significantly different by IUGR status. The Shannon index suggested there was no significant difference in alpha-diversity between IUGR and normal placenta tissues. At the taxa level, the placenta microbiota of IUGR patients had significantly higher prevalence of Bacteroidetes phyla, Desulfovibrio and Neisseria genus, and lower levels of Lactobacillus and Bifidobacterium genus. The IUGR samples showed significantly lower Firmicutes/Bacteroidetes ratios compared to AGA controls. In conclusions,distinctive placenta microbiota patterns, particularly the loss of potential beneficial Lactobacillus were found to be associated in placentas from IUGR pregnancies. Our results suggest that the placental microbiome is a potential biomarker for fetal and placental health during pregnancy. Less...