Developmental delay factsheet


Developmental milestones are skills that most children learn by a certain age. 

These milestone skills can include things like:

  • smiling
  • rolling over
  • first steps
  • first words.

Developmental milestones are generally used to track how a child is growing and developing. 

Your child may learn these skills:

  • earlier than other children
  • slightly later than other children
  • in a different order to other children.

Every child is different and will generally learn skills at their own pace within the developmental milestone windows. 

Developmental delay is when a child develops skills much slower than other children their age.

Global developmental delay is when a child has multiple skills that are slow to develop.

There is often no specific reason why a developmental delay happens. It can be more common in children who:

Social, environmental, and dietary issues can also affect a child's development.

Developmental delay does not always mean your child has a disability. Children with developmental delays can learn and develop at their own pace with extra support.

 Signs and symptoms

It is normal for babies and children to grow and develop at different speeds. It is important to remember that development milestones are a general guide. 

Every baby in NSW is given a personal health record, known as the “blue book”. 

The blue book is a guide to tracking growth, development, immunisations, and health checks from birth to age 5. It provides information about developmental milestones and what skills your child should learn at each age.

If you notice over several months that your child isn't developing skills at the same rate as other children of the same age, it is a good idea to seek help.

Speak to your local doctor or child and family health nurse if you have any concerns.


To diagnose a developmental delay, your local doctor will:

  • ask you some questions about your child’s health and development
  • do a physical check
  • do talk and play activities with your child to check their current skill development. 

Your doctor will refer you to relevant supports like:

  • specialist doctors
  • allied health professionals, like speech pathology and physiotherapy
  • support services. 

Speak to your doctor about Medicare plans for developmental delay, or accessing early intervention services through the National Disability Insurance Scheme (NDIS).


Developmental delay is treated with early intervention. Early intervention means providing support early to help children "catch up".
Early intervention can help you to: 

  • identify areas where your child needs support
  • access specialist health and support services.

Early intervention services will usually include therapy, education, and monitoring from professionals like:

  • occupational therapists
  • audiologists
  • physiotherapists
  • psychologists
  • speech pathologists
  • social workers.

The earlier your child’s developmental delay is identified and supports put in place, the better the outcome for your child and family. 

Last updated Tuesday 27th February 2024