Pervasive developmental disorder

Pervasive developmental disorders (PDD) are a group of disorders. There are five disorders in the group. These disorders all slow down the rate a child learns to talk and listen to others, as well as cause other problems.

The five disorders are:

• Pervasive disorder not otherwise specified (PDD-NOS)
• Autism
• Asperger Syndrome
• Rett syndrome
• Childhood disintegrative disorder (CDD).

The first three of these disorders are also called autism spectrum disorders. The last two are not common.

A child's parents might begin to notice signs of PDD when the child is a baby, and it usually appears before the child is three years old.

It is now possible to recognise many of these defects before birth. That is very important, because in time many defects will be curable in utero. We are moving into an era when the genetic code of babies may be tweaked in utero. See Nobel Prize awards since 2000 for some clues about this.