45% of ASD individuals have been found to have increased blood serotonin levels. It has been hypothesized that increased activity of serotonin in the developing brain may facilitate the onset of ASD, with an association found in six out of eight studies between the use of selective serotonin reuptake inhibitors (SSRIs) by the pregnant mother and the development of ASD in the child exposed to SSRI in the antenatal environment. The study could not definitively conclude SSRIs caused the increased risk for ASD due to the biases found in those studies, and the authors called for more definitive, better conducted studies. Confounding by indication has since then been shown to be likely. However, it is also hypothesized that SSRIs may help reduce symptoms of ASD and even positively affect brain development in some ASD patients. Diagnosis
Autism Spectrum Disorder a clinical diagnosis that is typically made by a physician based off reported and directly observed behavior in the affected individual. According to the updated diagnostic criteria in the DSM-5-TR, in order to receive a diagnosis of Autism Spectrum Disorder, one must present with “persistent deficits in social communication and social interaction” and “restricted, repetitive patterns of behavior, interests, or activities.” These behaviors must begin in early childhood and affect one’s ability to perform everyday tasks. Furthermore, the symptoms must not be fully explainable by intellectual developmental disorder or global developmental delay. There are several factors that make Autism Spectrum Disorder difficult to diagnose.
While employers state hiring concerns about productivity and supervision, experienced employers of autistics give positive reports of above average memory and detail orientation as well as a high regard for rules and procedure in autistic employees. The majority of the economic burden of autism is caused by lost productivity in the job market. From the perspective of the social model of disability, social model of disability, much of this unemployment is caused by the lack of understanding from employers and coworkers. Adding content related to autism in existing diversity training can clarify misconceptions, support employees, and help provide new opportunities for autistic people. As of 2021, the potential for new autism employment initiatives by major employers in the United States continue to grow. The most high-profile autism initiative in the United States, "Autism at Work" grew to 20 of the largest companies in the United States. However, special hiring programs remain largely limited to entry-level technology positions, such as software testing, and exclude those who have talents outside of technology. An alternative approach is systemic neurodiversity inclusion. Developing organizational systems with enough flexibility and fairness to include autistic employees improves the work experience of all employees. Epidemiology
The  World Health Organization (WHO) estimates that about 1 in 100 children have autism.