Endometrial Microbial Profile in Infertile Women with Chronic Endometritis: Intensified Culturomics and 16S rDNA Gene Sequencing.

BACKGROUND/

OBJECTIVES

Chronic endometritis (CE) has been linked to implantation failure, recurrent pregnancy loss, and endometrial dysbiosis with low Lactobacillus abundance. We assessed the endometrial microbiota in infertile women with CE and the added value of combining intensified culturomics with 16S rDNA NGS.

METHODS

Cross-sectional study with descriptive results of 15 endometrial biopsies analyzed in parallel by intensified culture and 16S rDNA (V3-V6) sequencing (RA threshold ≥ 5%).

RESULTS

Culture yielded growth in 13/15 samples (86.7%), whereas NGS reported findings in 15/15 (100%). NGS provided additional taxa beyond culture in 14/15 (93.3%), while culture identified taxa missed by NGS in 10/15 (66.7%). In both culture-negative cases, NGS detected ≥1 taxon. Lactobacillus spp. appeared exclusively by NGS in 26.7% of samples; Fannyhessea vaginae showed the highest mean RA by NGS and did not grow in culture, underscoring complementarity.

CONCLUSIONS

16S NGS complements intensified culturomics for characterizing the endometrial microbiota in CE, enhancing detection-especially when culture is negative-and supports a combined, clinically contextualized interpretation. Larger, controlled cohorts are warranted to validate diagnostic and prognostic utility.