The current literature shows growing evidence of a link between gender dysphoria (GD) and autism spectrum disorder (ASD). This study reviews the available clinical and empirical data. A systematic search of the literature was conducted using the following databases: PubMed, Web of Science, PsycINFO and Scopus; utilizing different combinations of the following search terms: autism, autism spectrum disorder (ASD), Asperger's disorder (AD), co-morbidity, gender dysphoria (GD), gender identity disorder (GID), transgenderism and transsexualism. In total, 25 articles and reports were selected and discussed. Information was grouped by found co-occurrence rates, underlying hypotheses and implications for diagnosis and treatment. GD and ASD were found to co-occur frequently - sometimes characterized by atypical presentation of GD, which makes a correct diagnosis and determination of treatment options for GD difficult. Despite these challenges there are several case reports describing gender affirming treatment of co-occurring GD in adolescents and adults with ASD. Various underlying hypotheses for the link between GD and ASD were suggested, but almost all of them lack evidence.

Several studies have suggested an overrepresentation of (symptoms of) autism spectrum disorder (ASD) among individuals with gender dysphoria. Three studies have taken the inverse approach in children with ASD and showed increased parent report of the wish to be of the opposite gender in this group. This study compared the self-reported wish to be of the opposite gender (one item of the Youth Self-Report [YSR] and the Adult Self-Report [ASR]) of 573 adolescents (469 assigned boys and 104 assigned girls) and 807 adults (616 assigned males and 191 assigned females) with ASD to 1016 adolescents and 846 adults from the general population. Emotional and behavioral problems were measured by the DSM-oriented scales of the YSR and ASR. In addition, the Children’s Social Behavior Questionnaire and the Adult Social Behavior Questionnaire were used to measure specific subdomains of the ASD spectrum to test whether specific subdomains of ASD were particularly involved. Significantly more adolescents (6.5%) and adults (11.4%) with ASD endorsed this item as compared to the general population (3–5%). In adolescents, assigned girls endorsed this item more than assigned boys. No significant gender differences were found in the adults with ASD. In addition, on all DSM-oriented scales of both the YSR and ASR, adolescents and adults with ASD who endorsed the gender item had significantly higher scores compared to those without. There were no significant associations between endorsement of the gender item and any specific subdomain of ASD, providing no evidence for a sole role of one of the ASD subdomains and endorsement of the wish to be the opposite gender.