Comparison of Vaginal Microbiota in HPV-Negative and HPV-Positive Pregnant Women Using a Culture-Based Approach

Abstract The purpose of this study was to conduct a comparative analysis of the composition of the dominant groups of vaginal microorganisms in healthy pregnant women and pregnant women infected with HPV using a microbiological culture-based method. The MALDI TOF MS method and 16S rRNA gene fragment sequencing were used to identify microorganisms isolated from healthy pregnant women (n=32) and pregnant women infected with HPV (n=24). It was found that vaginal secretion samples from both groups contained bacteria of 4 phyla: Bacillota, Actinomycetota, Pseudomonadota, Bacteroidota, and Ascomycota fungi. The most common microbial community in healthy pregnant women being CST I (p=0.0007), and CST V in pregnant women infected with HPV (p=0.0001). At the genus level, a total of 25 taxa were found in all samples, with Lactobacillus being the dominant genus overall. Escherichia (p<0.0001) and Prevotella (p=0.0001) concentrations were higher in HPV infected patients. When calculating the Pearson correlation coefficient for the phyla, it was found that Bacillota correlated negatively with HPV genotypes 16 and 51 (p≤0.05), but positively with HPV genotype 59 (p≤0.05), just like Actinomycetota (p≤0.05). Bacteroidota correlated positively with HPV genotype 56 (0.001<p<0.01), and Ascomycota correlated positively with HPV genotypes 39 and 51 (p≤0.05; 0.001<p<0.01). Pearson correlation coefficients between bacteria genera and HPV genotypes were statistically significant for the following genera: Lactobacillus, Streptococcus, Enterococcus, Gardnerella, Escherichia, Prevotella. The data obtained in our study indicates that the culture-based method is informative when assessing the qualitative and quantitative composition of the microbiota, as well as the risk of potential complications during pregnancy in women with HPV.