Alterations of the vaginal microbiome in healthy pregnant women positive for group B Streptococcus colonization during the third trimesterOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
Researchers compared the vaginal microbiome of 22 pregnant women who tested culture-positive for group B Streptococcus (GBS) against 22 culture-negative pregnant women, all in their third trimester in Ismailia, Egypt.
How was it studied?
Vaginal samples underwent V3-V4 16S rRNA next-generation sequencing, with alpha- and beta-diversity analysis and KEGG pathway prediction comparing the two groups.
What did they find?
GBS-positive women had significantly more diverse, less homogenous vaginal communities, with lower Lactobacillus abundance (56% versus 88%) and higher levels of Ureaplasma, Gardnerella, Streptococcus, Corynebacterium, Staphylococcus, and Peptostreptococcus anaerobius. L. iners remained the dominant species in GBS-negative women. Predicted KEGG pathways for host immune and endocrine signaling were enriched only in GBS-positive communities, while lipid and nucleotide metabolism pathways were enriched only in GBS-negative communities.
Why it matters
The findings suggest GBS colonization coexists with a less Lactobacillus-dominant vaginal microbiome, though the authors note these functional associations are inferred and need confirmation in larger cohorts.