What is the women's health data gap?

The women’s health data gap is the distance between how much data women’s bodies generate and how little of it reaches research that could improve care. It shows up in two numbers.

The funding side: across the 64 conditions that drive most of the women’s health gap, six women-specific conditions (premenstrual syndrome, menopause, maternal haemorrhage, hypertensive disorders of pregnancy, cervical cancer, endometriosis) account for 14% of that gap in disability-adjusted life years, yet received under 1% of the research funding granted to those 64 conditions in 2019–2023, according to a World Economic Forum and McKinsey Health Institute analysis of NIH World RePORT data.

The data side: menstrual tracking apps are thought to have been downloaded more than 200 million times, and the market is dominated by three of them, Flo, Clue and Period Tracker; Flo alone reported around 70 million monthly active users in mid-2024 (company figure). The raw material for understanding the feminine cycle exists at a scale medicine has never had before.

So why doesn’t the data reach research?

Because of where it lives and how it is governed:

• It sits outside medical privacy law. Consumer cycle-tracking apps are generally not covered by HIPAA, which applies only to health plans, clearinghouses, providers and their business associates, so their data carries none of the guarantees that make clinical data usable in regulated research.
• Its stewardship fails basic tests. A peer-reviewed review of the 23 most popular women’s mHealth apps found 20 sharing data with third parties, with practices that do not comply with the GDPR. Data collected this way cannot ethically anchor research.
• Meanwhile, regulated data is over-locked. As Nature warned when the GDPR took effect, institutions tend to “err on the side of caution” and restrict sharing beyond what the law requires; in Finland, the first European country to adopt a dedicated law on the secondary use of health data (in force since 2020), approved data permits fell an estimated 47% below the expected level in 2023.

The result: the most abundant new source of women’s health data is the least trustworthy, and the most trustworthy sources are the hardest to use.

Closing the gap without repeating the failure

The gap will not be closed by another app that hoards data, nor by regulation alone. It requires infrastructure where the data is research-grade because it is consented: each woman holds her own record, decides who accesses it and why, and can revoke that access at any time.

Health Data Safe’s Women’s Health project is building it with the FemTech ecosystem: high-quality, ethically sourced datasets on the feminine cycle, held under explicit consent on open-source infrastructure, governed by a Swiss non-profit foundation whose statutes treat health data as a common good.

Sources

• World Economic Forum and McKinsey Health Institute (2025). Blueprint to Close the Women’s Health Gap: How to Improve Lives and Economies for All, section 2.2.1 and Figure 5. weforum.org
• Rampazzo F, Raybould A, Rampazzo P, Barker R, Leasure D (2024). ‘UPDATE: I’m pregnant!’: inferring global downloads and reasons for using menstrual tracking apps. Digital Health 10. doi:10.1177/20552076241298315
• Flo Health (30 July 2024). Flo Health secures more than $200M investment from General Atlantic. Press release, company figure. flo.health/newsroom
• U.S. Department of Health and Human Services, Office for Civil Rights (2022). Protecting the privacy and security of your health information when using your personal cell phone or tablet. hhs.gov
• Alfawzan N, Christen M, Spitale G, Biller-Andorno N (2022). Privacy, data sharing, and data security policies of women’s mHealth apps: scoping review and content analysis. JMIR mHealth and uHealth 10(5): e33735. doi:10.2196/33735
• Nature (2018). Science needs clarity on Europe’s data-protection law. Editorial, Nature 557: 467. doi:10.1038/d41586-018-05220-y
• Brück O, Sanmark E, Ponkilainen V, et al. (2024). European health regulations reduce registry-based research. Health Research Policy and Systems 22: 135. doi:10.1186/s12961-024-01228-1