The diagnostic techniques of modern medicine provide increasingly detailed information about potential future health or disease trajectories. Affected individuals face the challenge of anticipating the significance of the respective probabilities for their subjective life perspectives and making concrete decisions regarding examinations or treatments. Gabriela Brahier examines, using the example of prenatal diagnostics, how affected women arrive at their individual test decisions. Based on a theologically informed by philosophy and social sciences, as well as a qualitative interview study, the author demonstrates that decisions are made based on authenticity-driven value syntheses, leading to far-reaching consequences for the understanding of personal autonomy and for the practice of genetic counseling.