BACTERIAL VAGINOSIS IN PREGNANCY - DISTRIBUTION OF BACTERIAL SPECIES IN DIFFERENT GRAM-STAIN CATEGORIES OF THE VAGINAL FLORA

Vaginal swabs for microbiological culture were taken from 174 pregnant women whose vaginal flora had been evaluated by Gram's stain; 50 had grade III flora (bacterial vaginosis, BV), 50 grade II (intermediate), 41 had vaginal flora graded as abnormal which then reverted to grade I (revertants) and 33 had normal flora (controls).The aim was to deter mine whether bacterial species isolated from women with grade II flora differed from those with grade III flora, Isolation of Lactobacillus spp, decreased from grade I to grade III and that of other aerobic and anaerobic bacterial species increased, There was little difference in the species isolated from women with grade II and grade III flora, bu t there was a distinct order in which organisms in different species i ncreased in numbers. The vaginal flora of revertants was intermediate between that of healthy controls and those with grade II flora. Coagul ase-negative Staphylococcus spp. were isolated from a greater number o f revertants than grade I controls but the incidence did not increase in grade II or grade III. Bifidobacterium spp. were isolated from a gr eater number of revertants than grade I controls and increased further in grade II and grade m. However, Gardnerella vaginalis and il Mycopl asma hominis were isolated from a much larger number of women with gra de III flora than the other groups. The conclusion is that grade II is a transitional phase between grade I and grade III and that some orga nisms such as G. vaginalis and M. hominis only reach large numbers in the late stage, The sequence of. appearance of the various bacterial s pecies may be a result of the pathophysiological alteration of the vag inal ecosystem associated with BV.