Researchers call for stronger regulation of period tracking apps

Period tracking apps may compromise users’ privacy and reproductive autonomy, researchers have warned.

A paper from Rotterdam School of Management, Erasmus University, published in the journal Contraception flags ethical concerns in the algorithms used to track menstrual cycles and fertility windows.

Researchers found that users are subject to data breaches and can be exposed to limited or biased information about their reproductive health.

Authors Maria Carmen Punzi and Tamara Thuis said: “It is essential that we pay attention to the ethical development and implementation of innovation when it applies to contraception.

“The influence of algorithms on users’ experience of their menstrual cycle and fertility is sometimes invisible but can still change behaviour related to it.”

The research identified gaps in data protection, with some apps sharing sensitive information on users’ sexual activity, menstrual symptoms, and reproductive health with third parties, often without their informed consent.

They found that users frequently lack understanding of how their data is being used, stored, and shared.

The research also identified that many algorithms used are trained on limited datasets that may not represent the full diversity of menstrual experiences across different demographics, ages, and health conditions.

This can lead to inaccurate predictions that disproportionately affect certain user groups, potentially impacting contraceptive and related health decisions.

Researchers at the University of Cambridge’s Minderoo Centre for Technology and Democracy have also raised issues with period tracking apps in a report published on 11 June 2025.

‘The High Stakes of Tracking Menstruation’, authored by Dr Stephanie Felsberger, says that menstrual tracking apps “turn personal health information into data points to be collected, analysed, and sold”.

Felsberger adds: “This data in the wrong hands could enable harms that go beyond reproductive health, like intimate partner violence, risks to job prospects, workplace monitoring, or health insurance discrimination.”

To mitigate potential harm, the report calls for the NHS and other public bodies, to develop their own cycle tracking apps to “engender trust in FemTech, mitigate privacy violations, and give people more agency over how their menstrual data is used”.

The report calls for stricter regulation of menstrual tracking data, enforcement of existing regulations, and improved governance and security of FemTech apps.

However Sue Khan, vice president of security and data protection officer at FemTech firm Flo Health, said that the University of Cambridge paper could make women “feel unsafe about the privacy of period tracking applications”. 

In an article on LinkedIn, Khan wrote: “We have never – and will never monetize or sell user data.

“We do not see personal data as a commodity, and categorically reject the notion that women’s health data should be treated as a goldmine for advertising.”

Flo became the first consumer women’s health app to achieve unicorn status in July 2024.

A spokesperson for FemTech app Luna told Digital Health News: “We built Luna to support teens through adolescence, and protecting their privacy is a fundamental part of that mission.

“We do not sell data and we do not share data with advertisers.”