Belfast startup launches AI period tracking tool

A Belfast-based femtech company has launched what it claims is the world’s first AI-powered menstrual tracking system that provides clinical-grade insights into period volume, clotting and cycle trends.

Joii’s technology, unveiled in Dublin, combines a specially designed menstrual pad with a mobile app to measure blood volume and clot size in millilitres – offering users more objective data than subjective terms like “heavy” or “normal” flow.

Heavy menstrual bleeding affects one in three women, yet diagnosis is often delayed due to vague language used to describe symptoms. While other femtech apps track symptoms and cycles, they do not directly measure menstrual flow.

Founder and chief executive Justyna Strzeszynska created Joii after experiencing her own challenges navigating menstrual health.

“Doctors would ask me about my menstrual flow, but I had no benchmark, much less a reliable way to measure it,” she said.

Joii’s system uses pad-scanning volume analytics – a first in women’s health. Users wear disposable pads, then scan them using the free app. Images are analysed using computer vision technology to assess blood volume, clot size and composition. Results are available instantly in millilitres, with reports on average flow and cycle trends.

“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,” said Strzeszynska. “We’re helping people see their periods clearly, for the first time.”

The company’s AI model was trained largely on synthetic data due to the lack of available real-world images. It was then tested across a range of lighting conditions and usage scenarios to ensure reliable results.

How Joii works:

• Wear Joii Pads – Specially designed for comfort and visual clarity.

• Scan with the Joii App – Users scan used pads through the mobile app.

• Get Insights – Immediate readings show menstrual volume (in millilitres), clot detection and flow trends.

Over time, the app builds personalised data that can support healthcare appointments and inform diagnoses. Joii is particularly aimed at people with heavy bleeding or those facing long diagnostic delays for conditions such as endometriosis, which can take up to 10 years to diagnose.

Joii is also the only product of its kind currently on the market. While some researchers have attempted to track flow manually using menstrual cups in small studies, there has been no consistent or scalable tool for widespread menstrual health monitoring – until now.

The technology is registered as a Class I medical device in the UK and protected by multiple patents.

Joii’s impact has been tested in two clinical and real-world studies, including one funded by the National Institute for Health and Care Research (NIHR). Users reported:

• 62 per cent improvement in communication with GPs

• 288 per cent increase in symptom screening efficacy

• 134 per cent rise in menstrual health literacy

A separate feasibility study found:

• 33 per cent improvement in abnormal symptom screening

• 52 per cent increase in period health literacy

• 36 per cent improvement in discussing symptoms with GPs

Among healthcare professionals:

• 88.6 per cent of GPs said Joii improved period-related conversations

• 87.6 per cent found it easier to identify abnormal or heavy bleeding

• 93 per cent said it supports diagnosis of heavy menstrual bleeding

• 88.6 per cent said they would use it in practice if NHS-approved

Dr Fatema Mustansir Dawoodbhoy, NHS doctor and clinical adviser to Joii, said: “This app will definitely offer me better insights into how the patient is feeling as I will be able to understand their symptoms variation throughout the month.”

Dr Kushal Chummun, consultant in obstetrics and gynaecology at the Rotunda and Connolly Hospital, added: “I think the app is really, really good.”

To date, Joii has raised €2.4m and is backed by EIT Digital through its equity portfolio. As part of the EIT Digital Open Innovation Factory, Joii worked with Finnish software studio Ikune to enhance user experience, integrating gamification features to improve retention and data quality.

Joii is also collaborating with research institutions to explore menstrual blood as a non-invasive diagnostic tool. Predictive AI models are being developed to support earlier detection of conditions such as endometriosis, polycystic ovary syndrome (PCOS) and anaemia.

Strzeszynska said the research “helps build a crucial bridge between data and the healthcare system, offering credibility to patient healthcare monitoring apps. It generates clinically relevant insights that can support more meaningful, evidence-based conversations with healthcare providers.”

The Joii app is free to download on iOS and Android. Joii Evaluation Pads retail at €6.95 and are available online at www.joiicare.com and in selected pharmacies and health stores.