Readability and Accessibility of Terms of Service and Privacy Policies for Menstruation-Tracking Smartphone Applications.

Over 100 million women track their menstruation using mobile applications (apps). In addition to comparatively unremarkable personal information such as height and weight, these apps collect intimate data like characteristics of vaginal discharge and cervical position. In exchange, many apps claim to predict the timing and duration of menstruation and windows of fertility. From this information, users may modify their sexual behavior based on their reproductive intentions. Though these apps are popular, news reports and prior studies reveal that user expectations about privacy and accuracy often do not align with the content of terms of service and privacy policies. In this article, we analyzed the readability and accessibility of terms of service and privacy policies for 15 popular menstruation-tracking apps. We found that information about data-sharing practices and accuracy is often neither easily accessible nor understandable. As a result, terms of service and privacy policies likely obscure material information about privacy and accuracy, posing safety and reproductive health risks to users. To date, no regulatory body oversees or approves the vast majority of menstruation trackers, leaving the market open to apps that vary widely in quality, accuracy, and levels of protection. We encourage health care professionals to ask their patients and clients about app use and understanding, encourage them to review relevant app-specific information, and discourage use as contraception when indicated. We conclude with recommendations for future research to establish the appropriate standards of disclosure that should govern these and similar types of smartphone-based consumer health technologies.