Delusional perception of a reborn baby doll as a biological child in a patient with intellectual disabilities

Abstract Maternity delusions (MDs) are a rare subtype of delusions involving false beliefs related to procreation. This report presents the first detailed account of MDs in a patient with intellectual disabilities (IDs), who firmly believed that a reborn baby doll (RBD) was her biological daughter. The 34-year-old woman, diagnosed with mild IDs, borderline personality disorder, and possible delusional disorder, also had type 2 diabetes, obesity, and risperidone-induced hyperprolactinaemia. Despite occasionally recognising that the RBD was not a real child, her belief persisted. This case highlights the challenges of interpreting MD in individuals with ID and attributing these symptoms to specific psychiatric disorders. The fluctuating conviction in the delusion raises questions about its stability and challenges existing diagnostic criteria, suggesting a need for a dimensional approach to delusions in this population. MD in patients with ID is a complex and challenging phenomenon, requiring careful consideration in diagnosis and management. Further research is needed to clarify the aetiology and course of MD in this population.