Level Zero Health bags £5.5, the largest Pre-Seed round raised by a European female-founded company

It's not every day that you hear about the application of a kind of life-changing tech and wonder why it hasn't always existed. 

Sensor-powered continuous monitoring has transformed the lives of millions of diabetics. But why isn't it used in other health applications?

Now, UK startup Level Zero Health is leveraging first-of-a-kind sensors to remotely and continually monitor hormone levels and advance hormone and reproductive health. The company is also building the world's largest hormone health dataset to unlock next-level insights, research and personalised care.

Today, the company announced a £5.5 million Pre-Seed funding raise. 

Level Zero Health was founded over a year ago by Ula Rustamova, ex-Palantir Enterprise Tech Lead and wearable startup founder, alongside Irene Jia, who developed medical devices at Philips. I sat down with the founders to learn more. 

Rustamova recalled:

 "I started in computer science at 15, launched a wearable device company at 16, and later worked at Palantir as an enterprise technical lead.

When I met Irene, we both had a shared frustration—healthcare hardware and data were huge bottlenecks, especially in women's health. That's where Level Zero was born."

Why hasn't continuous hormone monitoring been done before?

Although hormones play a critical role in our health as they regulate all bodily functions, for decades, clinicians have relied on laboratory blood tests or urine tests.

Jia explained that continuous glucose monitors have existed since 1999, but the enzyme-based sensing they rely on doesn't translate to hormones. 

"Hormones are volatile, and the only clinically trusted data source remains blood draws — which are invasive and provide just a single snapshot in time." Further, blood drawers require specialised equipment and expertise."

Urine tests aren't any better, according to Rustamova, because by the time your hormones go from your bloodstream to your urine, typically there's a 10 to 20-hour delay. 

Instead, Level Zero Health's DNA-based sensors detect hormone levels in interstitial fluid  — the fluid surrounding cells and tissues. 

The rise of aptamer tech in biosensing

Level Zero Health uses aptamers as the core component of its sensor. Aptamers are synthetic, single-stranded DNA molecules designed to bind precisely to specific targets (e.g., hormones). When they attach to a target, they undergo a detectable structural change (conformational folding), which can be measured via optical or electrochemical methods. 

•  FDA approval of the second-ever aptamer-based drug.
•  The first successful lab demonstration of a progesterone-detecting aptamer.
•  Proof that aptamer sensors can reliably measure hormones directly in human and animal blood over extended periods.
• The company has demonstrated remarkable progress in just under a year, validating its DNA-based sensors in simulated samples across 98 per cent of the human clinical range, far outpacing industry standards.

A new kind of wearable

The company has developed an initial patch that takes a biochemical snapshot from the skin, producing a colourimetric reaction that a camera can read. 

It's also working on its flagship product, combining biochemistry and nanotechnology in a sleek, minimally invasive wearable patch. Attached to the user's arm, the patch uses microneedles to gather data and delivers real-time measurements of stress and reproductive hormones.

This advancement could transform multiple areas of healthcare, including IVF, menopause and testosterone replacement therapy (TRT), to name just a few. Currently, women undergoing IVF require blood tests every two to three days for weeks. With over 2.5 million IVF cycles undertaken worldwide each year, this represents a significant testing burden. Similarly, testosterone deficiency, which impacts 10 to 40 per cent of men globally, requires regular in-clinic blood tests. 

According to Rustamova:

"This breakthrough in health technology has come about in a relatively short amount of time, but already we are seeing strong demand from customers who recognise the benefits of hormone monitoring not only because it allows patients to skip invasive and inconvenient lab tests, but also because it captures critical data inaccessible before."

During the interview, she revealed:

The largest Pre-Seed round raised by a female-founded company in Europe

"We just found out today — we hit the record for the largest Pre-Seed round raised by a female-founded company in Europe. €6.9 million. The key was positioning: we're not just a 'women's health' company but building a clinical-grade data platform for everyone."

Despite its early stage, Level Zero Health has already established an impressive pipeline of customers. It will use the funding for R&D, bringing the product to market and expanding its team with the best talent available. While initially targeting B2B clinical applications, the company has positioned itself for potential B2C and pharma expansion as well. 

Level Zero Health is backed by investors, including redalpine, HAX (SOSV), Entrepreneur First London, Unruly Capital, Exceptional Ventures, Samos, Anorak, Springbank Collective, DTX, Black Jays and Transpose Platform. 

It has also received funding from angel investors, including Aaron Styer, medical director at CCRM Fertility and an associate professor at Harvard Medical School, Joshua Klein, medical director at Extend Fertility and assistant professor in reproductive science at Icahn School of Medicine at Mount Sinai, and Charlie Bryant, CEO & co-founder of Simple Pharma. 

Philip Kneis, investor at redalpine and board member of Level Zero Health, said: 

"We did it for blood pressure and will do it again for hormones.

Continuous hormone measurement is one of the holy grails of diagnostics, and as fundamental science transitions to engineering, we couldn't be more excited to back Level Zero Health in their mission to transform hormone tracking with their novel biosensor - paving the way for a new era of personalised health management."

Funding will be used for R&D, hiring in the UK and US and bringing the product to market.

Jia contends, "We believe this will fundamentally change healthcare. It's not just about tracking—it's about unlocking entirely new ways to treat and understand the human body."

Lead image: Level Zero Health. Photo: uncredited.