Importance of Digital Health Data Privacy: The Hidden Dangers of Period-Tracking

Meta ‘eavesdropping’ case shows how period apps have become a data goldmine (Andjela Milivojevic/The Bureau of Investigative Journalism).

Worldwide, over 500 million users regularly trust menstruation-tracking apps with some of their most personal information. From tracking their most recent period to entering pregnancy attempts and sexual health details, many people use these applications to understand their cycles and achieve family planning goals. Largely viewed as a helpful health literacy tool, period-tracking apps can predict the start of future cycles, estimate fertility windows, and examine other factors, improving a user's awareness of their reproductive health. 

Yet these apps do not always live up to the trust given to them. As of January 2021, several action lawsuits were filed against Flo Health, a fertility tracking app, naming Google, Meta, and an analytics company, Flurry, as co-defendants. These lawsuits were consolidated in a single action, Frasco v. Flo Health, Inc. et al., ultimately arguing that Flo unlawfully shared users’ health data, such as menstrual cycle and pregnancy-related information, with these third parties. Flo, Google, and Flurry settled with plaintiffs before a verdict was reached by the jury, collectively paying $59.5 million while refusing to publicly admit to any wrongdoing. Meta, however, chose to proceed to a jury trial, where a California jury found it in violation of the California Invasion of Privacy Act. Despite repeated assurances that users’ entries were confidential, data was shared through software development kits (SDKs) incorporated into the app. 

These period-tracking apps are a part of a larger business industry of digital products focused on women’s health, commonly referred to as FemTech. Such products have an estimated market value of around $60 billion, representing a large investment and reliance on digital health tools. Primarily, menstruation and fertility data are used by companies in advertisements, profiting off the personal information of users. A Cambridge study cites that data on pregnancy can be over two hundred times more valuable for targeted advertisements than age, gender, or location. Becoming pregnant or having a baby marks a life event that majorly changes an individual's shopping habits. Knowing such precise data allows advertisers to target users, potentially gaining valuable consumers. Outside of pregnancy, period tracking can be further used to target users at specific points in their cycle, such as increasing advertisements for beauty products during the oestrogen or ‘mating’ phase. 

Moreover, the 2022 overturning of Roe v. Wade places an additional layer of potential dangers on the current concerns regarding reproductive health data privacy. Currently, at least 24 states have either banned or are likely to ban abortions, with eight of them, including Georgia, Texas, and Indiana, considering bills allowing an individual to face homicide charges for an abortion. In such circumstances, digital data can potentially be used to identify those seeking to end a pregnancy, with some apps even stating they may disclose a user's data to law enforcement or government agencies at request. Other factors, such as miscarriages, irregular menstrual cycles, or errors in use (such as forgetting to track a cycle), could also be mistaken for abortions, demonstrating how the issue of data privacy affects all users. This concern is especially high for young Black, Indigenous, and/or low-income individuals, who have historically been surveilled at higher rates than those who are white and/or higher-income. 

The high potential for period-tracking and other fertility apps to be valuable tools for understanding personal health, coupled with the vulnerability of their data, exemplifies the importance of protecting digital reproductive health data. For users, it is critical to be aware of the potential dangers regarding data privacy, finding a balance between personal autonomy and safety in the current legal climate.