The effect of treatment for vaginal yeast infection on the prevalence of bacterial vaginosis in early pregnancy.

Both bacterial vaginosis and candidiasis are commonly seen in pregnancy, with marked differences in pregnancy outcome. The aim of this study was to assess the effect of antifungal treatment on the prevalence of bacterial vaginosis in early pregnancy. This prospective randomized study included 126 women in early pregnancy with heavy vaginal yeast colonization and 88 healthy controls. Vaginal flora was evaluated on initial visit and on two check-ups for the presence of bacterial vaginosis. Half of the heavily colonized patients received an antimycotic agent (clotrimazole). The prevalence of vaginosis was compared among the three groups. Xi (2)-test and Fisher's exact test were used for statistical analysis. Three of 72 (4.2%) yeast-free controls, two of 79 (2.5%) yeast infected but not treated patients, and nine of 63 (14.3%) infected and treated patients presented with bacterial vaginosis 4 weeks after the initial visit. There was a statistically significant increase in the prevalence of bacterial vaginosis (p<0.03) in yeast infected and treated patients as compared to colonized and untreated patients. Treatment of candidiasis in early pregnancy may contribute to an increased rate of bacterial vaginosis.