Lack Of Oxygen At Birth Can Autism Occur From Lack Of Oxygen At Birth?

Can autism occur from lack of oxygen at birth? - lack of oxygen at birth

My older brother suffers from severe autism. Although there appear normal and can walk, if his intellectual abilities that a child must be constantly monitored, etc.
I do not know why my brother has autism, but once I heard my mother say, an aunt, such problems happened during the birth.
He was born by Caesarean section, and it seemed that the doctor 40 minutes late and still not enough oxygen during birth.

This may lead to autism?
I do not want to ask my mother, do not get their complaints.

Thanks