Composition of the maternal gastrointestinal microbiome as a predictor of neonatal birth weight.

Background: The biological mechanism by which the maternal gastrointestinal microbiota contributes to fetal growth and neonatal birth weight is currently unknown. The purpose of this study was to explore how the composition of the maternal microbiome in varying pre-gravid body mass index (BMI) groups are associated with neonatal birth weight adjusted for gestational age.

Methods: Retrospective, cross-sectional metagenomic analysis of bio-banked fecal swab biospecimens (n = 102) self-collected by participants in the late second trimester of pregnancy.