Four of those children were from outside the territory, but died in the ACT.

The ACT Children and Young People Death Review Committee released the 2018 annual report this week. The most common cause of death is of babies aged less than 28 days for medical reasons including extreme prematurity and birth defects, the report states.

Over the past five years the ACT has recorded the deaths of 137 children or young people. Eleven of those cases are still with the coroner.

There were 16 children who had come to the attention of Child and Youth Protection Services, 12 had siblings subject to child concern reports, and 39 were known to ACT Policing.

Of the 16 known to the protection service, eight were the subject of child concern reports but a further five had been the subject of a child concern report which was then upgraded to need investigation.

Half of them died aged zero to four and half were aged five to 17. Girls were represented more than boys in those known to the protection and justice system.

Children known to Child and Youth Protective Services or the police were considered vulnerable, but the figures do not account for the extent to which the child or their family was involved with these systems. They may have experienced a range of risk factors including domestic and family violence, parental substance misuse, mental illness and involvement with the criminal justice system, the report said.

Half of the deaths over the five-year period occurred due to medical causes.

The report stated the most frequent indicative cause of death for children aged 28 days to 14 years was attributed to medical causes. The second most frequent cause of death for this age group was unintentional injury or accident including transport accidents and drowning.

Suicide is the leading cause of death for young people aged 15-17. Over the past five years, there has been 10 deaths in children and young people due to self-harm. Extreme prematurity has taken the lives of 52 infants, and medical causes has caused the death of 78 children and young people.

There was a small number of deaths that were from an "unascertained" cause, and unintentional injury or accident, less than five for each category, that were from an "unascertained" cause.

Minister for children, youth and families, Rachel Stephen-Smith, said the death of any child or young person was devastating.

"I would like to take this opportunity to extend my condolences, and I am sure the condolences of this Assembly, to all families and friends affected by the death of a child or young person," she said.