Tiny Health has raised $33m in Series B funding to expand its gut and vaginal microbiome testing, research and clinical platform, alongside launching a new $5m research programme.
The US company, which started with gut microbiome testing for babies and mothers, now offers gut testing across the lifespan as well as vaginal microbiome testing.
The oversubscribed round was led by B Capital and brings Tiny Health’s total funding to $46m. Existing investors Spero Ventures, The Venture City and Overwater Ventures participated, alongside new investors including Black Opal Ventures, Denver Ventures, Pave Health Ventures, Alumni Ventures, Gaingels and Pari Passu Ventures.
The funding will support further clinical research and interventional studies, education for healthcare practitioners and expansion of Powered by Tiny, the company’s B2B platform.
Alongside the raise, Tiny Health has committed $5m to a new Microbiome Research Program, through which researchers, clinicians and scientific partners will be able to use its testing, data and research capabilities.
“What started as a solution for my own family has become the infrastructure for an entire industry,” said founder and CEO Cheryl Sew Hoy.
“This Series B round propels microbiome science as the foundational layer for the next frontier of medicine.”
From babies to the whole lifespan
Founded in 2020 and launched in 2022, Tiny Health initially focused on the first 1,000 days of life, when the gut microbiome is particularly malleable, launching gut microbiome testing for babies alongside gut and vaginal testing for mothers.
Since then, adult testing has now overtaken paediatric testing, while Tiny Health is expanding its research into areas including inflammatory bowel disease, menopause, GLP-1s and oncology drug response.
The company says it has built a longitudinal dataset of nearly 200,000 microbiome profiles and now works with more than 6,000 healthcare practitioners. Its B2B platform, Powered by Tiny, grew four-fold last year, with partners spanning healthcare and precision medicine.
It is also developing TinyAI, trained on its proprietary dataset to provide personalised guidance based on users’ microbiome results.
Alongside scale, Tiny Health is trying to build evidence for what can actually be done with microbiome information.
“Tiny Health believes the next breakthroughs in microbiome science will come from bringing more researchers and institutions into the field,” said Kimberley Sukhum, PhD, chief science officer.
“This investment will help generate new evidence and foster collaborations across the scientific community.”
A randomised controlled trial published in Pediatric Allergy and Immunology last year found that a targeted microbiome programme reduced the odds of eczema among participating babies born by C-section. Tiny Health says a second RCT is now underway.
This push towards clinical evidence is particularly relevant to its women’s health work. Tiny Health already offers vaginal microbiome testing, while its wider research programme is moving into menopause and other areas where the microbiome could potentially provide new information about health and treatment.
The raise also comes just two weeks after Evvy secured a $40m Series B to expand its work around the vaginal microbiome, including a deeper push into fertility and IVF.
The companies have different focuses - Tiny Health spans the gut and vaginal microbiomes across the lifespan, while Evvy is specifically focused on vaginal health - but both are now building beyond consumer testing into large longitudinal datasets, research and clinical applications.
The activity reflects a broader shift in the vaginal microbiome market, as companies move beyond simply identifying which microbes are present towards understanding how that information could inform diagnosis, treatment and care.
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