A microbiological survey has been carried out on 179 healthy, child-bearing aged, non-pregnant women, with the aim to evaluate the incidence of anaerobic non-spore forming bacteria in the normal vaginal flora. This group of bacteria has been isolated in 50.3% of women, with a clear prevalence of "anaerobic Streptococci " and Bacteroides, followed by Fusobacterium and Veillonella. No Propionibacterium, Eubacterium or Bifidobacterium have been isolated. According to many Authors the non-spore forming anaerobes must be considered opportunistic bacteria, responsible of many infections of the female genital tract, especially when associated with other aerobic or facultative bacteria. Antibiograms have demonstrated a wide spectrum of activity of chloramphenicol and clindamycin; although not widely distributed, antibacterial activity have also shown metronidazole, penicillins, cephalosporins and lincomycin.