Nugent Score (Bacterial Vaginosis Gram Stain)
Nugent score (Nugent 1991): Gram-stain morphotype counts for lactobacilli, Gardnerella/Bacteroides, and Mobiluncus give a 0–10 score where 7–10 indicates bacterial vaginosis.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Lactobacillus morphotypes
- 0 (4)
- Gardnerella / Bacteroides morphotypes
- > 30 (4)
- Curved gram-variable rods / Mobiluncus
- 1-4 (1)
Result: Nugent score 9 — bacterial vaginosis (7-10).
The tool opens with these values already filled in. Replace them with your own.
What the result means
- 0-3
- Normal vaginal flora.
- 4-6
- Intermediate flora.
- 7-10
- Bacterial vaginosis. Gram-stain morphotype scoring. A laboratory score, not a treatment order.
What you enter
- Lactobacillus morphotypes (points)
- Gardnerella / Bacteroides morphotypes (points)
- Curved gram-variable rods / Mobiluncus (points)
How this is calculated
Nugent RP, Krohn MA, Hillier SL. Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation. J Clin Microbiol. 1991;29(2):297-301. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.