Microscopic image (100 ×) of Gram-stained vaginal smears illustrating the different categories of vaginal microflora described:. a, b: grade Ia, i.e. mainly Lactobacillus crispatus cell types, plump quite homogeneous lactobacilli. c, d: grade Ib, i.e. non-L. crispatus cell types, long or short, thin lactobacilli. e, f: grade Iab, i.e. containing mixtures of L. crispatus and non-L. crispatus cell types. g, h: grade I-like, i.e. irregular-shaped Gram positive rods. i, j: grade II, i.e. mixture of Lactobacillus cell types and bacterial vaginosis-associated bacteria (Gardnerella, Bacteroides-Prevotella and Mobiluncus cell types). k, l: grade III, i.e. bacterial vaginosis.