Investigation of the vaginal microbiome at the time of delivery in a cohort of Indian women with term and preterm births using 16S rRNA gene sequencing to determine whether microbial diversity or specific taxa are associated with PTB in this underrepresented population, and contribution of population-specific data that can inform global strategies for the prevention of adverse pregnancy outcomes
Preterm birth is a leading cause of neonatal morbidity and mortality worldwide, with India alone contributing nearly 27 percent of the global PTB burden. Although alterations in the vaginal microbiome have been implicated in PTB. This study aimed to investigate associations between vaginal microbial profiles and PTB among pregnant women in Western India. The vaginal swabs were collected at delivery and analysed from 72 women admitted to a tertiary care hospital in Western India. Microbial DNA was extracted, and the V3-V4 region of the 16S rRNA gene was sequenced. Community composition, alpha and beta diversity, and differential taxonomic abundance were assessed using four independent bioinformatics pipelines to ensure analytical robustness. The vaginal microbiome was dominated by Lactobacillus, with no significant differences in alpha or beta diversity between term and preterm groups. Principal coordinate and unsupervised clustering analyses showed no group-wise segregation. The relative abundance of individual Lactobacillus species, including L. iners and L. helveticus, did not differ significantly between the two groups. This study found no major microbial shifts in the vaginal microbiome associated with preterm birth in this cohort of Indian women, suggesting that vaginal dysbiosis at the time of delivery may not be a principal driver of PTB in this population. These findings underscore the need for larger, longitudinal, and ethnically diverse studies using standardized methodologies better to understand the role of microbiome in PTB risk.