Objectives To determine the prevalence of Gardnerella vaginalis in women with normal vaginal flora.

Methods Women without symptoms or signs of vaginal infection and five or fewer lifetime sexual partners were recruited for a longitudinal study of vaginal flora. Negative Amsel criteria and a Nugent score of 0–3 were required for enrolment. Vaginal specimens were self-collected daily for Gram stain and every 3 days for PCR for G vaginalis for 30 days. Women completed daily diaries recording sexual activity, symptoms and menses.

Results Twenty women were recruited for the study with 19 completing all specimens and 1 lost to follow-up. During the 30-day study period, 13/19 (68.4%) of women had normal Nugent scores (0–3) whereas 6/19 (31.6%) of women had at least 2 days of Nugent scores in the intermediate range (p=0.09). Among the 19 women, 9 (47%) were negative for G vaginalis by PCR throughout the study period whereas 10 (53%) had at least one specimen that demonstrated the presence of G vaginalis by PCR. Of those women with intermediate flora on Gram stain during the course of the study 5/6 (83.3%) were positive for G vaginalis while 5/13 (38.5%) of those women with only normal Nugent scores were positive for G vaginalis. Thus, 61.5% of women with normal Nugent scores had no evidence of G vaginalis by serial PCR.

Conclusions Gardnerella may not be part of the normal flora in women with optimal vaginal health.