Association of asymptomatic bacterial vaginosis with endometrial microbial colonization and plasma cell endometritis in nonpregnant women

Objective This study was undertaken to determine whether asymptomatic bacterial vaginosis (BV) is associated with an increased risk of endometrial microbial colonization or plasma cell endometritis in nonpregnant women. Study design In this observational cohort study conducted between August 1995 and August 2001, microbial cultures (n = 769) and histopathology (n = 482) were performed on endometrial specimens obtained from women with a recent preterm or term delivery (83 ± 16 days). Endometritis was defined as the presence of plasma cells. BV was defined using Amsel and Nugent criteria. Results The study population was 71% black, 29% white, 69% single, and 31% had 12 years or more of education. Endometrial cultures were positive for at least 1 microorganism in 83% (n = 637/769) of the women and plasma cell endometritis was present in 39% (n = 190/482). BV was present in 26% (n = 191/722) by Amsel and 38% (n = 289/769) by Nugent criteria. Women with Nugent-BV (RR [relative risk] = 1.12, 95% CI 1.05-1.19) but not Amsel-BV (RR = 1.06, 95% CI 1.00-1.13) were significantly more likely to have a positive endometrial culture. A consistent and significant association was observed between BV (by Amsel or Nugent criteria) and an increased frequency of endometrial colonization with BV-associated microorganisms grouped and defined in various ways (RR ranged from 1.96-4.22). No association between BV and plasma cell endometritis was observed. Conclusion Asymptomatic BV is associated with a modest increased likelihood of endometrial microbial colonization and colonization by BV-associated bacteria but is not associated with plasma cell endometritis in nonpregnant women.