Meet Selena Elliott. She is 35 years old and received her diagnosis of autism in August last year.
She believes it was more difficult for her to get her diagnosis because she is a woman.
Statistics show more men and boys than women and girls are diagnosed as autistic.
The NAS says "women and girls...may be better at masking their difficulties in order to fit in with their peers and have a more even profile of social skills in general."
Selena is working with other families with autistic children and is passionate about raising awareness of autism in adults.
Here is her story: