Metagenomic characterization of the maternal prenatal gastrointestinal microbiome by pregravid BMI

Abstract

Objective: The incidence of women entering into pregnancy with BMI indicating overweight or obesity is rising with concurrent increases in adverse complications such as gestational diabetes. Although several studies have examined the compositional changes to the microbiome across BMI classifications, there has been no investigation regarding changes in microbial function during pregnancy.Methods: A total of 105 gastrointestinal microbiome biospecimens were used in this analysis. Biospecimens were sequenced by using the Illumina NovaSeq 6000 shotgun metagenomics platform.Results: Findings indicate an enrichment in microbiota from the phylum Firmicutes across all pregravid BMI groups with a decrease in α diversity in groups with BMI indicating obesity or overweight compared with a group with BMI indicating normal weight (p = 0.02). More specifically, women with BMI indicating obesity or overweight had enrichment in Bifidobacterium bifidum and B. adolescentis. Women with BMI > 25 kg/m 2 had a higher abundance of microbiota that support biotin synthesis and regulate epithelial cells in the lower gastrointestinal tract. These epithelial cells are responsible for host adaptability to dietary lipid variation and caloric absorption.Conclusions: Our analysis suggests that there are differences in microbial composition and function between BMI groups. Future research should consider how these changes contribute to specific clinical outcomes during pregnancy.

The Embodied Microbiome

“…Cadmium and polycyclic aromatic hydrocarbons were used as examples for biotransformations that had implications for both the pregnancy and the offspring. Driesbach, et al [22] using retrospective, cross-sectional metagenomic analysis found that maternal microbiome composition in the late second trimester was an effective predictor of birth weight. Maternal microbiome composition at 36 weeks of pregnancy was also shown to be a good predictor of immune cell composition in the newborn at birth.…”

“…For example, serotonin and dopamine levels and/or signaling are controlled by specific gut bacteria [49][50][51]. In addition, the important role of a balanced gut microbiome in fear extinction helps to protect against anxiety, depression, and mental illness [33] Table 1 illustrates the areas where our body's microbiota intercedes to affect our life and even our body's immediate afterlife [22,29,33,42, (Table 1).…”

“…The specific hologenome, particularly at the level of the microimmunosome, can determine offspring fitness and inflammationdriven risk to the offspring Preparation of the next generation in utero [22,29] The maternal microbiome affects not only the course of the pregnancy but also the fetal and eventually postnatal development of the offspring Infant maturation [55,56] The newborn-infant microbiome determines whether systems like the immune and neurological systems can fully mature (for normal function).…”