Overview

• The Cell Host & Microbe paper reports that Clostridium innocuum in early pregnancy is associated with higher risk of delivery before 37 weeks.
• Across two China-based cohorts, investigators analyzed stool and blood from 4,286 women in early pregnancy and 1,027 in mid-pregnancy using 16S rRNA and metagenomic sequencing.
• Statistical models identified 11 genera and one species tied to gestational duration or preterm status, with C. innocuum showing the strongest association.
• Laboratory work found an estradiol-degrading enzyme in C. innocuum, and mouse experiments showed the bacterium lowered estradiol by converting it to estrone.
• The authors note limited generalizability due to the cohorts’ geography and preterm prevalence and emphasize the need for validation before recommending monitoring or interventions.