Demystifying Menstrual Synchrony: Women's Subjective Beliefs About Bleeding in Tandem With Other Women

Abstract

Despite the empirical uncertainty about the existence of menstrual synchrony (i.e., the phenomenon where some women's menstrual cycles synchronize when they live in close proximity with one another), the persistence of beliefs in its existence permeate popular and medical discourses. Although there is a substantial body of scientific work on whether or not menstrual synchrony exists, far less work has examined why women believe in menstrual synchrony and the reasons they attribute to its existence (or not). Qualitative data from semistructured interviews with a diverse community sample of 20 women (mean age = 35.35, SD = 12.01) living in a large Southwestern U.S. city from a range of age, race, class, and sexual orientation backgrounds (40% women of color, 20% lesbian, 20% bisexual) were collected to examine beliefs about menstrual synchrony. Results revealed that women overwhelmingly endorsed the occurrence of menstrual synchrony both for themselves (90%) and for other women (95%). Four themes were associated with women's beliefs in menstrual synchrony: (1) connection to and hierarchy among other women; (2) menstrual synchrony as “magical” or “mysterious”; (3) menstrual synchrony as biological and animal-like; (4) managing and overcoming negative experiences with menstruation. Tensions between connection and dominance—and the contradictions and complications in women's modes of bonding with other women—are discussed, particularly as women fluctuated between shame and solidarity about their menstrual cycles. Menstrual synchrony offers one possible avenue to feel collective anger, and it highlights women's feelings about mysticism, science, and close female relationships.