Menstrual tracking applications (MTAs) are now a routine part of digital life and central to the growing FemTech industry. By turning intimate menstrual and reproductive details into data, they create new risks of privacy invasion, commercial misuse and state surveillance. This paper compares how four jurisdictions — namely the US (post Dobbs), Canada, the UK, the European Union (EU), and India — govern menstrual health data and the predictive claims made by MTAs. Through comparative legal analysis, regulatory gap mapping and doctrinal review, three weaknesses emerge. The first is inconsistent recognition of menstrual and reproductive data as sensitive or special category information requiring heightened safeguards. The second is limited algorithmic accountability for predictive features such as ovulation and fertility forecasts, despite their influence on personal health and reproductive choices. The third is fragmented cross-border enforcement that enables regulatory arbitrage and leaves remedies weak in practice. Case studies, including the Federal Trade Commission’s (FTC) action against Flo Health, the Canadian class action with oversight by the Office of the Privacy Commissioner (OPC), the UK Information Commissioner’s 2023 review of fertility tracking apps and India’s Digital Personal Data Protection Act 2023 read with the Digital Personal Data Protection Rules 2025 and Medical Device Rules 2017, illustrate both progress and persistent gaps. The paper advances a reform agenda built on five priorities: classify reproductive data as sensitive; mandate independent validation and audit of predictive claims; embed privacy by design with granular consent, minimisation and deletion by default; impose distribution safeguards at the platform level; and strengthen cross-border regulatory cooperation. It concludes that protecting reproductive autonomy requires recognising informational self-determination as a core right. This article is also included in The Business & Management Collection which can be accessed at https://hstalks.com/business/.
Jawed et al. (Sun,) studied this question.