What is developmental delay?

Developmental delay is the term used when a child does not progress as expected. For example, your child’s speech may lag behind other children. Or,your child may have been slow to learn to walk. In some children, developmental delay is suspected soon after birth because of feeding difficulties or unusual muscle tone. In other children, developmental delay is only suspected much later when learning or behavioural difficulties surface at school.

What causes developmental delay?

There are many different causes for developmental delay. It is a common condition affecting 1-3% of the population. The delay may be caused by a child’s genetic makeup (eg Down syndrome), by problems during pregnancy (eginfection), around the time of delivery, especially if very premature (eg bleedingin the brain), early infancy (eg meningitis) or later in childhood (eg head injury).
A cause can be found in about half of cases.

Why can it be useful to find a cause?

There are a number of benefits for you and your child to finding out what might be causing the developmental delay. These include:

  • Helping your child’s health professionals to understand the condition and how it may affect your child in the future
  • Helping your child’s health and education professionals to find the best ways to care for your child
  • Helping you to find the best way to care for your child
  • Addressing concerns you might have about events that happened before your child was born
  • Helping you find out whether any future children you or your family have could also have the condition

Assessment of developmental delay

A Paediatrician (a child specialist) usually does the assessment of developmental delay. The paediatrician will ask questions about your child’s medical history, examine your child, measure your child’s height, weight and head circumference, and assess your child’s developmental progress. Other professionals may be involved in this assessment and your child may be referred for hearing or visionassessment.

Your child may be offered some tests or further referrals, for example to a Paediatric Neurologist (a specialist who deals with the brain and nervous system) or geneticist (a specialist who deals with a person’s genetic makeup) to try to determine the cause of your child’s developmental delay.

What type of investigations are done for developmental delay?

There are many different types of test available. These could include:

Maternal infection tests – these are to check whether a mother had aninfection during her pregnancy that affected her child eg rubella

Chromosome analysis – chromosomes are structures in the body that contain genetic information. A chromosomal disorder can occur spontaneously (a once off occurrence) or it can be inherited from a parent. Looking at the chromosomes can help us identify hundreds of disorders that cause developmental delay

Specific genetic tests – there are thousands of genetic conditions that can cause developmental delay in a child. In order for the paediatrician or geneticist to select the appropriate tests on your child, a brain scan may be necessary

Samples may also be taken from parents to find out whether either parent is a carrier of the genetic disorder.

Not every child with developmental delay will be offered tests. There are many conditions for which there is no genetic test yet.

What if a diagnosis is made?

The Doctor will explain what the diagnosis means for you and your child eg what the common features of the condition are, whether there is any treatment for the condition, whether the condition can be passed from one generation to the next.

What if there is no diagnosis?

In spite of investigations, approximately half of children with developmental delay will not receive a specific name for their condition.

And finally…remember that developmental delay does not stop a child from having a full and rewarding life. Your child’s health and educational professionals aim to help your child have a life as enjoyable and fulfilling as possible.