Global developmental delay is when a child's progression lags significantly behind the progress of the child's peer group in several different areas. When a child is delayed, it means he or she hasn't acquired certain skills or reached milestones at the same time as other children of the same age. Some typical areas that are delayed in a child with a global developmental delay often include cognitive or thinking skills, motor skills, social and emotional, language and speech, and vision. There are several different possible causes for this type of delay.
As young children develop, certain abilities usually emerge within the same time frame or normal age range. These are called developmental milestones and include things like sitting up, walking, talking, and many others. When a child does not reach these developmental milestones within the average time frame, or close to it, he or she is considered delayed in that area. It is possible to be delayed in just one specific area, such as language and speech, and to overcome the delay with targeted interventions like speech therapy. A child with a global developmental delay, however, has fallen behind in most areas of normal development, and the delays are not easily overcome.
Children with global developmental delay may lag behind their peers in several areas by six months or more, and delays of several years in some areas are common. In some cases, these children can catch up with peers, but more frequently they are left with lasting deficits. Typically these children have significant cognitive delays, often with IQ scores that deviate significantly from a normal or average score.
Learning to talk and to understand spoken language often occurs much later than average when there is a global developmental delay present. Gross motor skills like walking or jumping, and fine motor skills such as writing, are often very difficult to acquire. Control of emotion and appropriate social interactions with others can be very challenging for these children. In many cases, there may also be problems with senses such as vision and hearing.
Although isolated delays in just one area are fairly common, cases of global developmental delay affect a very small percentage of the population. A possible cause is damage to the central nervous system from trauma, fetal alcohol syndrome, or other reasons. Chromosomal abnormalities such as Down's syndrome or fragile X syndrome can also cause global developmental delay. It can also be caused by some metabolic disorders or by severe health problems that may occur with premature birth. With early intervention and treatment, many of the effects can be minimized so that the child can live as normally as possible.