Fig. 3

Erythromycin treatment promotes vaginal dysbiosis. a Analysis of vaginal microbiota communities from paired samples before and following 48 hours of erythromycin treatment demonstrates transition from Lactobacillus spp. dominance (n =  = 10, 63%) towards intermediate (n = 4) or complete Lactobacillus spp. depletion (n = 2) whilst communities initially low in Lactobacillus spp. remain so. Erythromycin treatment did not reduce b richness, c diversity or d bacterial load. A sub-analysis showed that erythromycin treatment was associated with decreased e richness (P = 0.03) and f diversity (P = 0.03) in communities initially depleted in Lactobacillus spp., treatment but was associated with a significant increase in diversity (P = 0.01) in communities initially dominated by Lactobacillus spp. g Bacterial load was similar between subgroups. h Lactobacillus spp. abundant communities experienced a 40% reduction in Lactobacillus spp. post treatment (P = 0.004, Wilcoxon signed rank test). Inv. inverse, VM vaginal microbiota