Bacterial vaginosis as a risk factor for upper genital tract infection.

OBJECTIVE: The objective of this study was to determine whether the clinical diagnosis of bacterial vaginosis is associated with objective evidence of acute upper genital tract infection. STUDY
DESIGN: Women who either met the Centers for Disease Control and Prevention's minimal criteria for acute pelvic inflammatory disease or had other "nonclassic" signs of upper genital tract infection (i.e., atypical pelvic pain, abnormal uterine bleeding, or cervicitis) were evaluated with either an endometrial biopsy or a laparoscopy with endometrial and fimbrial biopsies for objective evidence of upper genital tract infection. Bacterial vaginosis was considered present if three of the four following criteria were found: (1) homogeneous gray-white vaginal discharge, (2) vaginal pH > 4.5, (3) positive "whiff" test result, and (4) the presence of > 20% of epithelial cells classified as clue cells. Patients were considered to have upper genital tract infection if they had histologic, microbiologic, or laparoscopic evidence of upper tract infection.
RESULTS: One hundred sixteen women were evaluated between August 1993 and March 1997 with complete evaluations. Objective evidence of upper tract infection was present in 56% (14/25) of women with the clinical diagnosis of bacterial vaginosis compared with 30% of women (27/91) who did not meet the clinical criteria (p = 0.015). Using logistic regression to control for confounding variables, we found that the presence of bacterial vaginosis was associated with a threefold increased risk of upper genital tract infection (adjusted odds ratio = 3.0, 95% confidence interval 1.2 to 7.6).
CONCLUSIONS: Bacterial vaginosis is associated with an increased risk of objective evidence of acute upper genital tract infection. Future prospective studies are needed to determine whether treatment of bacterial vaginosis can reduce the risk of ascending infection.