Why Ida Tin and SPRIND are building the future of continuous hormone monitoring

The founder of Clue discusses the vision behind SPRIND's €40 million Hormone Challenge and why no single startup can solve the problem alone.

Our hormones shape everything from fertility and menopause to cardiovascular health, cognition, mood, immunity and metabolism. Yet most of what we know about hormones comes from occasional blood, saliva or urine tests that offer only brief snapshots of a constantly changing system. And despite their central role in health, many fundamental questions about female hormonal physiology in particular remain unanswered.

This is the gap that Ida Tin wants to close.

The founder of Clue is leading a €40 million Hormone Challenge at SPRIND, Germany's Federal Agency for Breakthrough Innovation, which supports ambitious scientific and technological breakthroughs with the potential to create entirely new industries.

The challenge aims to accelerate the development of continuous hormone monitoring technologies capable of measuring hormones in real time, while helping to build the foundations of a new field.

The idea is not a new one for Ida. She first started thinking about hormone sensors much earlier in her career.

“We tried to build a hormone sensor 20 years ago,” she told FutureFemHealth. “I’ve been looking at this space for a long time. It’s kind of happening, but it’s happening slowly.”

Applications are now open to startups, researchers and technical teams across Europe and Israel. Selected teams will receive funding, mentorship and support over the course of the three-year programme as they work to develop technologies capable of continuously measuring hormones.

And for Ida, the ultimate opportunity goes far beyond building a sensor.

“[This is a chance to] not just try to build one company, but try to build an industry,” she said. “I think that’s amazing.”

The problem with hormone snapshots

Today, hormones are typically measured through blood, urine or saliva tests.

While these tests can be useful, they provide only snapshots in time.

“The challenge is that it’s really hard to understand a curve when you have just a couple of points,” Ida explained. “Even if you have a point every month, it’s still really difficult.”

That lack of longitudinal data leaves huge gaps in our understanding of female physiology.

"It's just phenomenally mind-boggling that we have so little understanding of our hormonal system,” she said.

“We don’t have teenagers when they start their reproductive journey, understand their levels, and then understand how that maybe even affects them at the end of their lives.”

The implications extend far beyond fertility.

Ida points to unanswered questions around cardiovascular disease, Parkinson’s disease, cognitive decline, the gut microbiome and hormone replacement therapy.

“Hormones are kind of like the operating system of the body,” she said. “They affect our brain, our bones, our cognitive abilities, our mood, our reproductive health, our immunity.”

“We really don’t understand yet” many of these relationships, she said.

Why hasn’t this happened already?

So if the opportunity is so significant, why don’t continuous hormone monitors already exist?

Part of the answer is that the science is extraordinarily difficult.

“The concentrations that you have to be able to measure reliably are extraordinarily small,” said Ida. “It’s like a sugar cube in an Olympic-sized swimming pool.”

Female sex hormones are among the hardest molecules to measure continuously. They are present at very low concentrations and behave differently from easier analytes such as glucose and cortisol, which have attracted much of the attention in biosensing to date.

There are also non-technical factors too.

“What we consider important scientific questions to pursue is also formed by our culture and our gender norms,” Ida said.

The result is a field that has remained fragmented despite years of research and growing interest from startups.

Why SPRIND is taking a different approach

The SPRIND programme focuses only technologies capable of directly measuring hormones. According to the challenge criteria, participating teams must measure the hormone of interest itself rather than relying on surrogate physiological signals such as heart rate or temperature.

And rather than backing a single company, the programme is designed to support multiple technical approaches simultaneously while encouraging collaboration across the emerging ecosystem.

Ida believes that approach is essential.

When she looks back at the early days of Clue, she argues that the biggest challenge was never competition from other startups.

“The biggest challenge was to educate the market, educate the VCs, change culture,” she said.

She sees a similar challenge emerging in continuous hormone monitoring.

For the field to succeed, companies will need to solve not only technical problems but also manufacturing, regulation, clinical adoption, user experience, reimbursement and education.

“That’s why we need ecosystems,” she said.

The dataset may be as important as the sensors

Underpinning the creation of an ecosystem is a focus on building a shared reference dataset as part of the SPRIND programme.

Alongside the sensor development work, participating teams will contribute towards creating a common foundation for understanding hormone levels across different ages, ethnicities, life stages and health conditions.

According to Ida, this is not something any individual startup could realistically build alone.

“There are different hormones, different body fluids, different ages, different ethnicities, different conditions, different times of the day,” she said. “It’s really difficult for one startup to build that.”

The hope is that the dataset will outlive the programme itself and provide a trusted benchmark against which future hormone monitoring technologies can be validated. Ida argues that today's reference ranges are often so broad that they can be difficult to interpret meaningfully.

Building the infrastructure for female physiology

Ida’s vision is that continuous hormone monitoring is a foundational layer for future healthcare.

“When I think about modern medicine, I kind of get this picture of it being built on this backdrop of a healthy white man,” she said.

"And our bodies just look totally different."

Continuous hormone data, she argues, could help enable more personalised medicine, improved disease prevention, digital twins, new approaches to drug discovery and even AI models built around female physiology.

In Ida’s view, better hormone data could ultimately help medicine move beyond a one-size-fits-all model and towards a deeper understanding of how physiology changes across sex, age and life stage.

That is ultimately why she chose continuous hormone monitoring as the focus for SPRIND’s first major women’s health initiative.

"There is enough to be done in women's health," she said. "But from all the time I spent in femtech, I felt this was a really huge data gap that we have."

By 2029, when the programme ends, Ida hopes it will have done more than produce promising technologies. She hopes it will have helped create the foundations for an entirely new industry.

“The ultimate goal,” she said, “is that this data makes a difference for women out there.”

• Applications for the SPRIND continuous hormone challenge are open until 26 June 2026 at 6pm CEST. For more information and to apply visit SPRIND.