Nugent's scoring system for diagnosis of bacterial vaginosis

The score is determined by the average number of each morphotype seen per oil-immersion field but varies with the type of bacteria. Excluding Lactobacillus morphotypes, a score of 0 means no morphotypes are present; 1, 0 to 1 morphotype present per high-power field; 2, 1 to 4 morphotypes present; 3, 5 to 30 morphotypes present; 4, 30 or more morphotypes present. A total score of 7 to 10 is indicative of bacterial vaginosis infection, 4 to 6 is indeterminate, and 0 to 3 is normal. (Total score = lactobacilli score and Gardnerella vaginalis score and Bacteroides species score and curved gram-variable rod score.)