A patient returns for the third time with the same complaint. Culture showed nothing alarming. The previous treatment made little difference. You are confident something is wrong — but the tools available to you cannot name it.
This is not an unusual case. It is the case that exposes the gap between what we measure and what is actually happening.
Knowing who is present is one thing. Knowing how much is another.
Every healthy woman’s vaginal flora contains opportunistic organisms in small numbers: Gardnerella, mycoplasmas, Candida. Their presence alone is not disease.
What creates the clinical picture is when these organisms expand at the expense of lactobacilli until the balance between them breaks. Culture and microscopy answer only the question of presence — a question that does not separate the healthy woman from the symptomatic one, because the same organism is found in both.
The limitation is well documented. A recent review of bacterial vaginosis diagnostics concluded that Amsel’s criteria and Nugent scoring — while remaining a historical reference — do not adequately reflect the modern understanding of BV as a polymicrobial condition, and that inter-observer variability in microscopy compounds the difficulty [1].
What quantitative measurement adds
FEMOFLOR® II is a real-time PCR assay, but it does not stop at yes or no. It measures the proportion of each microbiota group relative to total bacterial load.
The normal reference: protective flora — lactobacilli and bifidobacteria — should represent ≥80% of the total. When that proportion falls, the report shows which group has taken its place: anaerobic, aerobic, mycoplasmal, or fungal.
This is precisely where the clinical value lies. Bacterial vaginosis, aerobic vaginitis, and mixed dysbiosis may look similar in your clinic, yet call for different therapeutic approaches. Proportion is what separates them.
The evidence? A study of 331 women presenting with vaginal discharge applied this technique alongside Nugent criteria and found a clear, statistically significant reduction in lactobacilli proportion among women with bacterial vaginosis compared with healthy controls [2]. A further study of 45 discharge cases concluded that true bacterial diversity is not always captured by Nugent scoring alone and requires nucleic acid amplification to detect [3].
A detail worth noticing
Not all lactobacilli are equal.
L. crispatus produces the most lactic acid and is therefore the most stable and protective. L. iners is weaker at maintaining a low pH and is considered a transitional type, more inclined to shift toward dysbiosis.
The patient whose lactobacilli appear adequate in total, but are mostly L. iners — her relapse after successful treatment is not a surprise. It is a logical consequence of the flora’s own composition. And it is something neither culture nor microscopy will show you.
What the test covers
Quality controls — human genomic DNA and total bacterial load, distinguishing a true negative from an inadequate specimen.
Protective flora — Lactobacillus spp. with species-level typing, and Bifidobacterium spp.
Opportunists — aerobic and anaerobic groups associated with BV, AV and mixed dysbiosis, including Gardnerella, Atopobium, and Streptococcus agalactiae against a pregnancy-specific reference.
Mycoplasmas and yeasts — Mycoplasma hominis, Ureaplasma spp., Candida spp.
Obligate pathogens — Chlamydia trachomatis, Mycoplasma genitalium, Neisseria gonorrhoeae, Trichomonas vaginalis.
Selected viruses — HSV-1, HSV-2, CMV, and high-risk HPV types.
Where it genuinely helps
The test replaces nothing, and is not for every visit. Its value shows in:
• Recurrent or unexplained discharge after inconclusive conventional work-up
• Differentiating BV, AV and mixed dysbiosis before selecting therapy
• Recurrent candidiasis where species identification matters
• Preconception assessment, infertility work-up, and selected obstetric cases
• Documenting restored balance after treatment, rather than relying on symptom resolution
And what it does not do
The test does not provide antimicrobial susceptibility. Where therapy must be guided by an antibiogram — as in some aerobic vaginitis cases — culture remains necessary.
Clinical interpretation remains yours alone. The report offers measured microbiological data, not a ready-made diagnosis.
References
1. Savicheva AM. Molecular Testing for the Diagnosis of Bacterial Vaginosis. Int J Mol Sci. 2023;25(1):449.
2. Savicheva AM, Krysanova AA, Budilovskaya OV, et al. Vaginal Microbiota Molecular Profiling in Women with Bacterial Vaginosis: A Novel Diagnostic Tool. Int J Mol Sci. 2023;24(21):15880.
3. Baykushev R, Raykova V. Multiplex Real-Time PCR Method as a Reliable Test in the Routine Microbiology Study of Vaginal Microbiome in Women with Genital Tract Discharge. J of IMAB. 2024;30(3):5648–5654.
4. DNA-Technology. Femoflor® — instructions for use and clinical significance documentation.
