Apps tracking menstruation a goldmine for personal data merchants – report

Smartphone apps that track menstrual cycles are a “gold mine” for consumer profiling, collecting information on everything from exercise, diet, and medication to sexual preferences, hormone levels, and contraception use.

That’s what a new report from the University of Cambridge’s Minderoo Centre for Technology and Democracy says.

The report adds that the financial worth of this data is indeed “vastly underestimated” by users who almost willingly supply companies – which are always profit-driven – with highly intimate details in a market lacking regulation.

“Menstrual tracking applications turn personal health information into data points to be collected, analysed, and sold. This poses risks and harms for users and society, as menstrual tracking data can be used to control people’s reproductive lives,” said Dr. Stefanie Felsberger, author of the report.

For example, in the United Kingdom, police forces may be able to check tracking apps and medical records related to reproductive health, while in the United States, following the reversal of Roe v Wade, the second Donald Trump administration is actively defunding life-saving reproductive and sexual health care.

That’s why cycle tracking app (CTA) data in the wrong hands could result in risks to job prospects, workplace monitoring, health insurance discrimination, or cyberstalking – and limit access to abortion.

“Menstrual cycle tracking apps are presented as empowering women and addressing the gender health gap,” said Felsberger (PDF).

“Yet the business model behind their services rests on commercial use, selling user data and insights to third parties for profit. There are real and frightening privacy and safety risks to women as a result.”

Investigations by media, non-profit, and consumer groups have revealed CTAs sharing data with third parties ranging from advertisers and data brokers to tech giants such as Facebook and Google.

CTA data is of especially high commercial value as these apps are primarily targeted at women aiming to get pregnant. No other life event is linked to such dramatic shifts in consumer behavior.

In fact, data on pregnancy is believed to be over two hundred times more valuable than data on age, gender, or location for targeted advertising.

The three most popular apps alone had an estimated quarter of a billion global downloads in 2024. So-called femtech – digital products focused on women’s health and wellbeing – is estimated to reach over US$60 billion by 2027, with cycle tracking apps making up half of this market.

In the UK and the European Union, period tracking data is at least considered a “special category”, as with that on genetics or ethnicity, and has more legal safeguards.

But in the US, data about menstrual cycles has been collected by officials in an attempt to undermine abortion access. Despite this, data from CTAs are regulated simply as “general wellness” and granted no special protections.

“Menstrual tracking data is being used to control people’s reproductive lives,” said Felsberger.

“It should not be left in the hands of private companies.”

According to her, commercial apps could at the very least include delete buttons, allowing users to erase data in the app as well as the company servers. This would help guard against situations – from legal to medical – where data could be used against them.