Irish femtech startup brings medical-grade period tracking to the masses

For decades, women have been told to "track their period" — but with what, exactly? A calendar app? A notebook? Vague memories? Dublin-based femtech startup Joii says: that's not good enough.

Backed by clinical studies, medical device certification, and nearly €2.5 million in funding, Joii has launched a first-of-its-kind solution combining an AI-powered app with a smart, scannable menstrual pad.

The result? Period tracking that's no longer guesswork. It's data. It's science. And according to founder Justyna Strzeszynska, it's long overdue.

"Doctors would ask me about my menstrual flow, but I had no benchmark — much less a real way to reliably and accurately measure it."

How does it work?

The magic lies in a three-step process that's both simple and clinically powerful:

• Wear the pad: Joii's evaluation pads are comfy, discreet, and specially designed to clearly show volume and clots.
• Scan with the app: After use, scan the pad with your phone's camera using the Joii app.
• Get insights instantly: The app uses computer vision to analyze the pad, providing real-time data on blood volume (in millilitres), clot size, and symptom trends.

Over time, Joii builds a personalised profile of each user's cycle — giving people actionable insights they can take straight to their GP.

And it works in real life, not just in the lab. Joii's AI was trained with synthetic data and rigorously tested in various lighting conditions to mimic everyday usage.

"Users get an instant report detailing blood volume in millilitres, average flow, clot size, and symptom trends."

Why does it matter?

Because menstrual health is often misunderstood, ignored, or dismissed — even in healthcare settings.

• 1 in 3 women experience heavy menstrual bleeding, yet many don't get diagnosed for years — if at all.
• Standard tracking apps don't actually measure flow volume. They log moods, symptoms, ovulation — but not what doctors really need to know.
• Diagnosing conditions like endometriosis or PCOS can take up to a decade.

Joii changes that by putting clinical-grade data in the hands of patients and doctors.

"For too long, women have been told to just 'track their period' without any real tools to measure what's actually happening. With Joii, we're changing that."

And it's not just anecdotal. In early studies:

• 62% of users said Joii improved communication with their doctor.
• 288% increase in symptom screening efficacy.
• 134% jump in menstrual health literacy.

Clinicians are also on board.

"This app will definitely offer me better insights into how the patient is feeling," said Dr. Fatema Mustansir Dawoodbhoy, Clinical Advisor to Joii. "I think the app is really, really good," added Dr. Kushal Chummun, Consultant in Obstetrics and Gynaecology.

The context

Let's not beat around the bush — women's health has been sidelined for far too long.

• Just 2% of the UK's medical research budget goes to pregnancy, childbirth, or female reproductive health.
• Most period tracking is still stuck in the stone age — either based on symptoms or completely subjective.

Joii isn't just a product — it's a quiet rebellion against the status quo.

The startup's tech is certified as a Class I Medical Device in the UK, covered by multiple patents, and ready to go mainstream.

It's also part of a growing movement to treat menstrual blood as a diagnostic goldmine. Joii's research collaborations aim to use AI to detect early signs of anaemia, endometriosis, and PCOS — just from a period pad.

And here's the kicker:

• 88.6% of GPs in clinical trials say Joii improves conversations about periods.
• 93% believe it supports better diagnoses of heavy bleeding.
• 87.6% say it makes abnormal symptoms easier to spot.

With support from EIT Digital and Finnish studio Ikune, Joii has also layered in smart design and gamification to boost user engagement and retention — making it as sticky as it is smart.

The app's free while the pads cost €6.95. That seems like a small price to pay for finally being able to answer your doctor with more than a shrug.