RESUMEN
The transgender population has higher rates of psychiatric disorders and stigma within medical settings. Literature suggests that gender-affirming care is the standard when working with such patients. There are limited studies regarding treating these patients with severe mental illness (SMI). This article explores how to treat SMI that impacts patients' reality to the point where their assigned sex cannot be acknowledged. The case presented is that of a transgender woman, where clarification of her natal sex was crucial to treatment. The patient denied her natal sex, endorsing a history of miscarriage. Studies on treatment of transgender SMI patients are limited. Gender-affirming treatment is the standard of care for these patients. Training how to ask pertinent questions and communicate effectively is necessary to prevent misdiagnosis, unnecessary treatment, and agitation. [Psychiatr Ann. 2023;53(5):221–223.]