In this article, we investigate the role of scientific and patient narratives on perceptions of the medical debate around gestational diabetes (GDM) testing. Among medical scientists, we show that the narrative surrounding GDM testing affirms that future research and data will lead to medical consensus. We call this narrative trajectory the "deferred quest." For patients, however, diagnosis and their subsequent discovery that biomedicine does not speak in one voice ruptures their trust in medical authority. This new distrust creates space for patients to develop a Frankian quest narrative where they become the protagonist in their story. Additionally, across these different narratives, we observe how character is constructed and employed to negotiate trust. We conclude that healthcare providers should assess the narrative trajectory adopted by patients after diagnosis. Also, we suggest that providers acknowledge the lack of medical consensus to their patients. This veracity would foster women's sense of trust in their provider as well as allow women to be active interlocutors in a debate that ultimately plays out in their deliberation about their body, pregnancy, and risk.