Characterization of Vaginal Microbiota Profiles in Native Korean Women Related with High Risk Pregnancies

Vaginal microbiota may be important for prognosis of pregnancy because dysbiosis in vaginal microbiota during pregnancy seems to be related with preterm birth (PTB) or pregnancy loss. Previously, the residence of a Lactobacillus-poor in vagina and intrauterine infection by diverse anaerobes ascending from vagina have been reported to be associated with undesirable delivery outcomes. However, there is no specific research on vaginal microbiota profiles using pyrosequencing analysis and its potential association with high risk pregnancies of Korean women. Total 500 Korean women's vaginal swabs were collected in order to determine the community state types (CST) of Korean women. Among them, 137 samples (from 70 non-pregnant and 67 pregnant women) were further analyzed by Roche/454 GS Junior Pyrosequencer. Microbiota profiles were created by PCR amplification and pyrosequencing of the 16S rRNA V1~V3 variable region. Three distinct CSTs can be classified based on the dominant vaginal microbes: CST I (Lactobacillus crispatus dominated), CST III (Lactobacillus iners dominated) and CST IV (diverse species of anaerobes). Among 67 pregnant women, 12 women had undesirable pregnancy outcomes (4 miscarriages and 8 preterm births). Women who gave a birth at term had L. crispatus as a major microbe of vaginal microbiota. In contrast, L. iners was the dominant vaginal microbes in miscarriage women. Most of the vaginal microbiota profiles (n=6/8) of women who had experienced PTB could be classified in CST IV and showed diverse bacteria including anaerobic vaginal genera such as Atopobium, Streptococcus, Gardnerella and Escherichia. These genera were previously reported to be related with preterm delivery. This study provides information regarding characteristics of the vaginal microbiota structures of Korean women related with high risk pregnancies. On-going investigation of the vaginal microbiota structures of Korean pregnant women is needed for prediction of adverse pregnancy outcomes.