She Invented A Smarter Tampon. Then Came Three Walls To Climb

A diagnostic tampon that detects cervical cancer-causing HPV strains is peer-reviewed, NHS-approved, and TIME-recognized. Yet Daye founder Valentina Milanova pitched 400 investors to raise $28 million in venture capital plus $4 million in grants. Google classifies her device as a contraceptive, which makes advertising harder and more expensive. Her story exposes the fourth wall women's health founders hit after crossing the funding, data, and innovation gaps: a commercialization system that wasn't built for them.

The tampon in question detects high-risk HPV strains that cause 99.8% of cervical cancer cases, has been peer-reviewed in the Journal of Clinical Microbiology, and was named a TIME Best Invention of 2024. Yet, Google has classified Daye's diagnostic tampon not as a medical device, not as a diagnostic tool, but as a contraceptive.

No one, in the history of medicine, has used a self-sampling device as a contraceptive. Google’s categorization is ridiculous.

Most femtech founders hit a funding gap, a data gap, or an innovation gap. Valentina Milanova, founder and CEO of Daye, hit all three, crossed each one, and then discovered a fourth wall: a commercialization system built by and for incumbents that treats a medical-grade diagnostic tampon as a hygiene product, a pharmaceutical or, apparently, birth control.

You’d think that a diagnostic tampon capable of helping eradicate cervical cancer deserves the same seriousness as everything else venture capital already funds. You’d be wrong.

Milanova founded Daye in London in 2017 after discovering that existing tampon manufacturers had no interest in raising their own standards. Tampons used internally required less regulatory documentation than most over-the-counter medications. No continuous quality management. No batch testing for heavy metals or microbiological content. One-time biocompatibility data, and that’s enough.

So she built her own manufacturing facility in Bulgaria, designed her own production standards, and applied for ISO 13485, GMP, and EU MDR certification—the same standards used for surgical instruments. She received FDA 510(k) clearance for her menstrual tampon and went on to develop a second-generation diagnostic tampon capable of at-home HPV and STI detection. The company has raised approximately $28 million, plus roughly $4 million in grants, according to Milanova.

Getting there required pitching 180 investors for the seed round and more than 400 for the Series A. Milanova is direct about why. "Daye is everything that the investor does not like,” she said. “It is a medical and diagnostic devices company, which has its own manufacturing, so there's a hardware component in heavily regulated industries led by a single female founder who's Eastern European."

Annie Theriault, founding partner at CBIV and a Daye board member for four years, frames the same reality from the other side. "Daye does the unglamorous, capital-intensive work most of the category avoids—clinical trials, in-house medical-device manufacturing, real regulatory clearances,” she noted. “That combination is rare in femtech, and it's what builds a durable business rather than a momentary one."

Tatum Getty, a partner at Thena Capital, an investor in Daye, wrote that the company’s approach addresses a fundamental barrier to adoption. "Valentina didn't ask women to adopt an entirely new behaviour; she took a product millions already know and trust and expanded what it could do,” she said. “That's the kind of healthcare innovation that has the greatest chance of changing outcomes because it removes friction instead of creating it. Daye has paired that simplicity with rigorous clinical evidence, which is a combination we rarely see with an enormous market opportunity."

What Milanova has learned over nearly a decade is which parts of her own company to conceal in a pitch. CPT code eligibility, which Daye received last year and which opens a path to insurance reimbursement, actually frightened investors who immediately thought about a 14 to 90 day billing cycles depending on the payor. The tampon's ongoing use in clinical trials to detect ovarian and endometrial cancer in the US and UK prompted the question "why aren't you focused?" The medical database Daye has built from vaginal, menstrual, and hormonal health outcomes, shared pro bono with academic institutions, generated no interest at all.

The global femtech market was estimated at $39.29 billion in 2024 and is projected to reach $97.25 billion by 2030. None of that projected growth changes what an investor said to Milanova before one recent pitch meeting, a comment that encapsulates the problem. He opened by telling her she looked prettier in person than in her LinkedIn photo. She has made a deliberate decision to stop being angry about moments like that and put the energy somewhere productive. It is not a small decision.