Gardnerella vaginalis has started a controversy due to different interpretations of its clinical significance, taxonomic position and reaction to Gram stain. The organism was initially called Haemophilus vaginalis. However, it lacked some of the characteristics required by the Haemophilus species. Back then it was called Corynebacterium vaginale. It was later changed to Gardnerella vaginalis when a new genus became necessary (Catlin, 1992). This article will focus on the characteristics of G. vaginalis and how it is identified.G. vaginalis cells are Gram-negative to Gram-variable. These cells are nonmotile, small, pleomorphic rods that do not have typical endospores, flagella, or capsules. In smears of vaginal fluid, the Gram reaction can vary from positive to negative (Catlin, 1992). G. vaginalis is seen in uncrowded areas in a Papanicolaou preparation. Their morphology and staining reactions are influenced by the physiological state of the bacteria. Both coccobacilli and longer forms are present in 24-hour cultures of G. vaginalis on blood agar. Their average dimensions range from 0.4 x 1.0 to 1.5 µm. The cells do not elongate into filaments although they can reach dimensions of up to 2-3 µm (Catlin, 1992). Cultures on vaginalis agar showed numerous short gram-negative rods. A starch-containing medium showed more pleomorphic, gram-variable, clustered, and beaded cultures. 48-hour cultures of blood samples from patients with G. vaginalis have been reported as mostly Gram-positive (Catlin, 1992). G. vaginalis is beta-haemolytic on media containing human or rabbit blood but not on sheep blood agar. Hemolysis is enhanced by anaerobic incubation. Catlin (1992) reports that many different media have been used to isolate G. vaginalis from clinical specimens. The most successful media are... middle of paper... bacteria and mycoplasmas. Further support for this conclusion was obtained in a study of the Grivet monkey as a model of bacterial vaginosis. Bacterial vaginosis is treated with antibiotic drugs (CDC). Metronidazole is commonly used. Treatment with metronidazole does not adversely affect lactobacilli, so they are able to recolonize the vagina and reduce the risk of late-stage recurrence (Catlin, 1992). Cephalosporins available in the late 1970s were not very active against G. vaginalis.G. vaginalis is still a mystery and is continually investigated. Research is underway to identify its causes and pathogenicity. Improved means and methods used for isolation and identification are useful in obtaining answers. The development of a suitable animal model for bacterial vaginosis is one of the challenging areas for future investigations (Catlin, 1992).