This article investigates the mediatization of responsibility in the context of health care decision-making and biological citizenship. The analyzes how Danish parents navigate the pervasiveness, polysemy, and media logic of health communication, and how the authority and legitimacy of certain types of health communication play into their sense of responsibility. The study consists of interviews with 18 Danish parents who were in the process of deciding or had recently decided on whether to give their child the human papillomavirus (HPV) vaccine. This study draws on mediatization theory, sociological theory of responsibility, and research on health communication to illustrate the media-centered conditions that shape parents’ decision-making processes. We find that the pervasiveness and polysemic nature of the information available about the vaccine creates an imperative to understand the information while parents also have to navigate the media logic regarding media’s motivation for presenting information about HPV vaccines in certain ways. As a consequence, parents’ decision-making responsibility as biological citizens is undergoing significant changes that place increasing responsibility on the parents in this study.