Chronic endometritis and fertility: A binomial linked by microorganisms

To explore the relationship of microorganisms with chronic endometritis, comparing findings in our region with reports in the literature.

Retrospective descriptive study of 110 endometrial biopsies from women treated for fertility problems at a tertiary hospital from 2021 through 2022. Results were compared between women with and without chronic endometritis.

Chronic endometritis was diagnosed in 50.91 % (n = 56) of the women, with at least one microorganism detected in 57.14 % (n = 32). Microorganisms other than Lactobacillus spp. were more often (p = 0.009) observed in women with chronic endometritis. The most frequently isolated non-Lactobacillus microorganism was Gardnerella vaginalis (10.71 %), followed by Streptococcus anginosus (8.93 %), S. agalactiae (5.36 %), and Corynebacterium amycolatum (5.36 %). There was a trend towards a lower frequency of Lactobacillus spp. in women with chronic endometritis (p = 0.08672).

The endometrial microbiota significantly differs between women with versus without chronic endometritis, observing a reduced proportion of Lactobacillus spp. and proteobacteria and an increased proportion of Gardnerella spp. in the former. However, further research is needed on the relationship between microorganisms and chronic endometritis to assist therapeutic decision-making and improve the reproductive prognosis.