Distribution of sTfR concentrations according to vaginal microflora status. Box-and-whisker plots of the sTfR distributions according to vaginal microflora status during early pregnancy. The thick line represents the median sTfR value, the horizontal box lines the 25th percentile and 75th percentile, and the outer short horizontal lines the boundaries of the sTfR range. Healthy vaginal flora is defined as grade I or lactobacilli-dominated microflora on Gram stain (corresponding to a Nugent score 0 – 3) and disturbed vaginal flora is defined as grade II and grade III flora, this is mixed or gram-negative rods-dominated microflora on Gram stain (corresponding to a Nugent score ≥4).
Verstraelen et al. BMC Infectious Diseases 2005 5:55 doi:10.1186/1471-2334-5-55