A report by the Minderoo Centre (University of Cambridge), published on June 10, 2025, warns of an alarming phenomenon: period-tracking apps, with over 250 million downloads globally in 2024, are collecting extremely personal data. They detail your sexual, medical, exercise, and condom use habits and sell this information to third parties without clear or secure consent. This makes you a target for intrusive advertising, medical or employment discrimination, and even reproductive surveillance, especially in countries where abortion is restricted.

What data do they collect?

·       Sexual activity, contraceptive use, emotions, exercise habits, and mental health.

·       Cycle frequency, fertile phases, medication schedules, and more.

Immediate Risks

·       Personalized advertising : your hormonal phase is detected to suggest products.

·       Discrimination : Insurers and employers can use data to limit your access to insurance or jobs.

·       Reproductive surveillance : In the U.S., registries have been used to restrict abortions.

Alternatives and solutions

·       The report calls for public entities such as the NHS to develop trustworthy apps, with clear consent and ethical use of data.

·       On Reddit, users recommend open-source applications like Drip , which store data locally and offer greater privacy.

Tips to protect yourself

·       Review the permissions: do not grant access without understanding what is being collected.

·       Opt for apps with encryption or local storage.

·       If you use a commercial app, delete your data before uninstalling it and disable sharing with third parties.