In this paper we present PeriodShare, a speculative design proposing a wireless menstrual cup that automatically quantifies and shares menstrual data on social networks. We suggest that PeriodShare is a design fiction that uses both crowd-funding rhetoric and the form of a rather clumsy DIY project to create a particular fictional universe that (1) speculates on a potential near future of quantification of menstruation, and through this (2) encourages to reflection on the dynamics of contemporary technology paradigms like the politics and culture of self-Tracking, sharing, and intimate data. As a research through design project and by using these communication threads, PeriodShare thus uses menstruation as a trope to investigate social, cultural and political issues of intimate technologies.