Gestational diabetes is associated with change in the gut microbiota composition in third trimester of pregnancy and postpartumOriginal 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?
This study examined whether gestational diabetes mellitus (GDM) is associated with changes in gut microbiota composition. Researchers profiled the gut microbiota using 16S rRNA gene amplicon sequencing of the V1-V2 region. Sampling occurred at two time points: the third trimester of pregnancy and about 8 months postpartum. Insulin and glucose homeostasis were assessed with a 75 g 2-hour oral glucose tolerance test during and after pregnancy.
Who was studied?
The cohort included 50 pregnant women with gestational diabetes mellitus and 157 normoglycaemic pregnant women, all assessed in the third trimester and again roughly 8 months postpartum. This gives a total study population of 207 women followed longitudinally across the perinatal period. The abstract does not specify additional demographic details such as age range or geographic origin.
What were the most important findings?
Gut microbiota composition differed between women with GDM and normoglycaemic women at multiple taxonomic levels, including phylum and genus. Actinobacteria at the phylum level and the genera Collinsella, Rothia, and Desulfovibrio were more abundant in the GDM cohort. Desulfovibrio is a sulfate-reducing bacterial genus capable of producing hydrogen sulfide, so its enrichment points to altered sulfur metabolism accompanying GDM. Seventeen species-level operational taxonomic units differed in abundance with GDM, and after adjusting for pre-pregnancy BMI, five of these remained differential, with enrichment of Faecalibacterium and Anaerotruncus species and depletion of others.
What are the greatest implications of this study?
The findings suggest that GDM is associated with a distinct gut microbiota signature that is detectable in late pregnancy and that some features may persist or relate to metabolic status postpartum. The enrichment of Desulfovibrio, a sulfate-reducing, hydrogen-sulfide-producing genus, alongside Actinobacteria-level shifts, suggests altered sulfur metabolism could be part of the metabolic perturbations linked to GDM. Because some associations remained after adjusting for pre-pregnancy BMI, the gut microbiota changes appear connected to GDM independent of baseline body weight. These results support further investigation of the gut microbiota, and sulfur-metabolizing taxa in particular, as potential contributors to or markers of glucose dysregulation in pregnancy.