I'm just testing this idea. We got a premature son 2 years ago. He was born in the 29th week.
If it seems promising, and people can answer the question properly, I will include it in the next Aspie-quiz.
Officially, there is strong comorbidity with ADHD, 20-40% on very premature children. This is currently explained as "damage" due to the premature birth, but I think this is incorrect. ADHD is a genetically based condition.
If I can link premature birth with the Aspie-axis in Aspie-quiz, I would have disproved this idea. It seems much more likely that the autistic genes themselves cause increased risk for premature birth.
It might be interesting to also include too late birth. Another of our sons were born 2 weeks too late.