© 2019 Elsevier Ltd Researchers have increasingly examined the menstrual cycle as a potential source of day-to-day variation in women's cognitions, motivations, and behavior. Within this literature, several lines of research have examined the impact of the menstrual cycle on women's engagement in activities that could negatively affect their health (alcohol and tobacco consumption, sexual behavior, risk recognition). However, findings have been mixed, leaving it unclear whether women may expose themselves to more health-related risks during certain phases of the cycle. We conducted a meta-analysis of 22 published and four unpublished studies (N = 7529, https://osf.io/xr37j/). The meta-analysis revealed shifts across the menstrual cycle in women's sexual behavior with others and risk recognition (higher in ovulatory phase), whereas there was no consistent pattern of difference for alcohol and cigarette consumption. These findings help to clarify the proximate physiological and evolutionary mechanisms underlying women's health-related risk-taking and may inform new interventions.