The diagnostic category pervasive developmental disorders (PDD), as opposed to specific developmental disorders (SDD), refers to a group of five disorders characterized by delays in the development of multiple basic functions including socialization and communication. 

Symptoms:

Symptoms of PDD may include communication problems such as:
Difficulty using and understanding language
Difficulty relating to people, objects, and events; for example, lack of eye contact, pointing behavior, and lack of facial responses
Unusual play with toys and other objects


Difficulty with changes in routine or familiar surroundings
Repetitive body movements or behavior patterns, such as hand flapping, hair twirling, foot tapping, or more complex movements
Unable to cuddle or be comforted, due to negative experiences of child abuse.

Children who have been raped, violated sexually, abused verbally, and lack a father figure in their lives, can become victims to Autism (Pervasive developmental disorder). 

Mothers who have been raped, smoked, used drugs, (pharmaceutical drugs), addicted to alcohol, prostitution, and verbally abused, rejected or mistreated during their pregnancy, are likely to give birth to a child suffering from Autism.