A lactic-acid-producing resident that dominates one of the most common and most acidic vaginal community types. Explore its illustrative 3D model, human context, and sources.
Ravel and colleagues sequenced the vaginal microbiota of 396 asymptomatic North American women representing four ethnic groups and identified five community state types. Community state type I was dominated by L. crispatus and occurred in 26.2% of participants, and communities belonging to group I had the lowest median pH at 4.0 ± 0.3, against 5.3 ± 0.6 for the non-Lactobacillus-dominated group IV. PHAC describes Lactobacillus species generally as Gram-positive rods or coccobacilli that occasionally form short chains, non-spore-forming, non-motile, chemo-organotrophic and microaerophilic, and as part of the normal flora of humans and animals, generally regarded as safe for use in food. This profile describes a resident organism, not an infection.
The association between L. crispatus dominance and a low vaginal pH is a description of community states in a cross-sectional cohort, not evidence that supplementing this species produces a health outcome for an individual. PHAC notes that lactobacilli are generally regarded as safe in food and that infections are uncommon, but records rare bacteraemia and septicaemia in people with cancer, diabetes, AIDS, valvulopathy or transplants, where translocation from the gastrointestinal tract may occur.
Lactobacillus crispatus · Two rounded rods suggest an occasional short chain. Curled culture appearances are not generalized to every cell. This is a species-informed teaching diagram; colours, proportions, envelope spacing and internal detail are illustrative. The model uses muted illustrative colours; stains, colony pigments and microscopy colourization are not natural cell colours. Anatomy is enlarged for phone viewing. Morphology reference: Lactobacillus spp. · pathogen safety data sheet.
Source check: 2026-09-20. Educational content; independent scientific review remains pending.