Population-adjusted numbers, demographics and mental health among children and adolescents referred to the Norwegian National Center for Gender Incongruence over two decades.

Over the last decade, there has been a sharp increase in young people seeking medical treatment for gender dysphoria/gender incongruence (GD/GI). The aims of this study were to calculate yearly population-adjusted numbers of children and adolescents referred to the Norwegian National Center for Gender Incongruence (NCGI) at Oslo University Hospital (OUS) from 2000 to 2022; to describe the demographic characteristics and prevalence of psychiatric diagnoses, self-harm and suicide attempts among the referred from 2000 to 2020; and to investigate time trends. The study used data from the Gender Incongruence Registry for Children and Adolescents (GIRCA) in Norway. All persons under 18 years (n = 1258) referred to the NCGI between 2000 and 2020 were included: 68.4% assigned female gender at birth (AFAB) and 31.6% assigned male gender at birth (AMAB). We found a sharp increase in referrals to the NCGI favouring AFAB over AMAB. Nearly two in three (64.5%) had one or more registered psychiatric diagnoses. Self-harm was registered among 35.5%, and 12.7% had attempted suicide. Registered psychiatric diagnoses were significantly (p ≤ 0.001) more prevalent among AFAB (67.8%) than AMAB (57.4%). The number of registered diagnoses per person decreased significantly over time, with an average reduction of 0.02 diagnoses per person per year. Although there was a downward time trend in registered diagnoses per person, the total mental health burden among children and adolescents with GI emphasizes the need for a holistic approach.