When Flo App launched as a simple period tracking app, few could have predicted its evolution into one of the world’s largest contributors to women’s health research. Today, with 22 million research participants across its studies, the company is systematically addressing centuries-old gaps in medical understanding of women’s bodies.
The scale is staggering: over 22 million participants have contributed to Flo’s research initiatives, making it uniquely positioned to surface insights that traditional clinical trials often miss. This isn’t passive data collection – participants explicitly consent to contribute to formal research studies that undergo ethical approval and peer review.
The need for such research is critical. According to Harvard Medical School, less than 1% of published medical studies focus on menopause, with perimenopause likely even more neglected. This research gap has real consequences: over 90% of women have never received education about menopause in school, and more than 60% feel uninformed about what to expect.
Flo’s landmark study on menstrual patterns included data from over 19 million users aged 18-55, making it the largest study of its kind. Until this research, most studies only included women up to age 45, leaving a significant knowledge gap about cycles and symptoms in older women. The findings challenged existing assumptions, revealing that cycles get slightly longer from age 18 to around 21-22, then gradually shorten by about two days between ages 22 and 45, before lengthening again after 45.
The research has yielded practical insights that directly improve women’s lives. Studies found that women with shorter, more regular cycles showed increased sexual motivation, while research on workplace productivity revealed that 48.4% of women don’t feel supported by their managers regarding menstrual cycle issues, and 94.6% report no workplace benefits addressing these needs.
What makes this research particularly valuable is its real-world nature. As Yella Hewings-Martin, senior research scientist at the company that successfully resolved legal challenges, explains: “Within every group of scientists, you have complementary expertise because you don’t want clones of the same thing. You have scientists come together as a collective with slightly different areas of expertise.” This multidisciplinary approach combines insights from epidemiology, behavioral science, health economics, and reproductive biology.
The company’s commitment extends beyond data collection to active hypothesis testing. In randomized controlled trials with universities including Johns Hopkins and the University of Virginia, Flo demonstrated that app usage improved health literacy scores, reduced PMS symptom burden, and decreased work absenteeism among users with premenstrual conditions.
A recent study published in npj Women’s Health revealed surprising patterns in perimenopause symptoms. Psychological symptoms like anxiety and irritability peaked in women aged 41-45, while physical symptoms like hot flashes were most prominent in women aged 51-55. Over half of women aged 30-35 reported moderate to severe symptoms typically associated with perimenopause, challenging assumptions about when these changes begin.
The research team currently includes over 20 dedicated scientists and collaborates with 15+ members of Flo’s scientific advisory board. This investment in scientific talent, combined with the platform’s massive user base willing to participate in research, creates an unprecedented opportunity to answer questions that have puzzled researchers for decades, even as legal proceedings revealed the importance of proper data handling and while other companies faced jury verdicts over privacy violations.
By transforming millions of individual health journeys into collective scientific knowledge, Flo demonstrates how digital health platforms can serve dual purposes: providing personalized support to users while generating insights that advance medical understanding for all women.