Why Precision Microbiome Profiling Is the Right Tool for Vaginal Health Testing

For decades, the dominant approach to microbiome analysis has been DNA sequencing, either broad 16S amplicon sequencing or the more detailed shotgun metagenomics. These methods were designed for the gut, where there is abundant microbial material and relatively little human DNA contamination. The vaginal microbiome is an entirely different environment, and it requires a fundamentally different approach.

Precision Microbiome Profiling (PMP™) technology was built specifically to overcome the challenges that make sequencing ill-suited to vaginal specimens.

The Problem with Sequencing for Vaginal Specimens

Sequencing technologies, whether 16S amplicon or shotgun metagenomics, were proven tools for gut microbiome research. In that context, they shine: samples are rich in microbial DNA and relatively free of human contamination. But vaginal and skin specimens present two fundamental challenges that expose the limitations of sequencing:

Challenge 1: Low microbial biomass. Vaginal swabs contain far fewer bacterial cells than gut samples. In sequencing workflows, this matters enormously: the sample is sub-sampled multiple times before any reading occurs, amplifying stochastic errors. The less you start with, the less reliable the result.

Challenge 2: High host DNA contamination. Vaginal epithelial cells shed constantly, flooding the sample with human DNA. For shotgun sequencing, this drives up cost dramatically and degrades accuracy, because the instrument must sequence enormous quantities of human DNA before encountering enough microbial signal.

Arne Materna, CEO of our partner laboratory for our Vaginal Microbiome test explains: "The moment the sample becomes sparse, shotgun sequencing quickly struggles — sensitivity drops, reproducibility suffers, and costs rise. For routine clinical testing, it simply isn't viable.”

PMP™ is unaffected by both of these challenges. It uses multiplexed quantitative PCR, targeting specific microbial species directly, which means host DNA is invisible to the assay, and low microbial biomass does not degrade sensitivity or reproducibility

Speed and Accuracy: Where PMP™ Excels

Two of the most critical requirements for any clinical test are turnaround time and quantitative accuracy. On both metrics, PMP™ decisively outperforms sequencing-based alternatives.

In head-to-head studies, PMP™ was compared directly against shotgun metagenomics and 16S sequencing using both high-diversity gut samples and low-biomass skin samples, the most challenging conditions for any method. The findings were unambiguous: PMP™ closely mirrored shotgun metagenomics (R² = 0.91 for relative abundance), while 16S sequencing significantly underperformed at both taxonomic resolution and quantitative accuracy.

Why Absolute Quantification is paramount.

Perhaps the most clinically significant advantage of PMP™ is one that is easy to overlook: absolute quantification. Sequencing methods only return relative abundances — they can tell you what proportion of the detected microbiome a species represents, but not how much of it is actually present.

This limitation, known in the scientific literature as compositionality, can lead to false discoveries in clinical trials and diagnostic applications. Consider this scenario:

The compositionality problem — a clinical example.  Imagine a probiotic treatment is given to a patient with vaginal dysbiosis. The probiotic Lactobacilli species colonise rapidly, increasing the total bacterial load. In relative terms, the pathogen's share of the microbiome appears to decrease — it looks like the treatment is working against the pathogen. But in absolute terms, the pathogen's count has not changed at all. The patient's infection risk remains exactly the same. Sequencing would call this a success; absolute quantification reveals the truth.

The principle that makes PMP™ valuable in vaginal health trials also makes it a powerful tool for any clinical application where microbial load, not just presence, is the meaningful variable.

The Pelvic Relief Vaginal Microbiome panel

Our PMP™ Vaginal Health Panel covers 47 bacterial species and 6 fungal species, selected to enable insight into the health or dysbiosis of the patients microbial environment, and to guide interventions and clinical decision making.

At a glance, we include the key Lactobacillus species that support health (L. crispatus, L. iners, L. gasseri, L. jensenii and others); BV-associated microbes (including Gardnerella vaginalis, Prevotella species, Mobiluncus, Megasphaera and BVAB organisms); organisms associated with aerobic vaginitis (including Escherichia coli, Streptococcus agalactiae, Staphylococcus aureus, Enterococcus); and Candida strains responsible for vulvovaginal candidiasis (C. albicans, C. glabrata, C. tropicalis and others).

To summarise: the right tool at the right time.

Vaginal microbiome conditions are prevalent, recurrent, treatable, and chronically underdiagnosed.  The technologies available until now either lacked the speed and cost-effectiveness for routine use, or lacked the accuracy to be trusted in clinical applications. PMP™ changes that.

By combining sub-species resolution, absolute quantification, low biomass tolerance, and a turnaround measured in days rather than months, at a competitive price, PMP™ is the first microbiome profiling technology that genuinely meets the requirements of routine clinical testing for women's health.

The science has always known that the vaginal microbiome matters. Now we have the tool to act on that knowledge.