Sudden unexplained death in childhood

What is sudden unexplained death in childhood?

Different terms can be used to describe sudden deaths in children. The charity SUDC UK provides information and an explanation of these, together with resources for families and professionals, on its website: SUDC UK – Sudden Unexplained Death in Childhood

The term ‘sudden unexpected death in childhood’ is typically used to describe the death of a child, aged between one and 17 years, who died suddenly and whose death was “not anticipated as a significant possibility 24 hours before the death”. Once all investigations into the death are completed, these deaths are divided into those where there is a clear diagnosis (referred to as ‘explained’ deaths) and those where there is not a clear diagnosis (‘unexplained’ deaths).

The National Organization for Rare Disease in the United States emphasises that sudden unexplained death in childhood (SUDC) “cannot be predicted or prevented at this time” and that these deaths currently “elude our scientific understanding”.

“Sudden infant death syndrome” (SIDS) is the term used to describe the “sudden and unexplained death of an apparently healthy baby” aged under 12 months.

This short briefing focuses on SUDC and highlights where further information on the matter can be found. March is SUDC awareness month and 18 March 2026 is National SUDC day.

Research in SUDC

The National Child Mortality Database (NCMD) published a report in December 2022 on Sudden and Unexpected Deaths in Infancy and Childhood (PDF). It marked the first time data had been collected and presented nationally, for England, about all unexpected child deaths (and not just those that remained unexplained). Data from the report on the number of SUDC is presented below.

While emphasising that “sudden and unexplained death in childhood is a rare event”, the NCMD report (PDF) noted that there was a “lack of [an] evidence base surrounding the unexplained deaths of older children”, with evidence relating to “contributory factors” highlighted as particularly “weak”.

‘Contributory factors’ are not the immediate or underlying cause of death but are significant medical conditions, behaviours and/or environmental circumstances that increased the risk of death.

The NCMD made ten recommendations in its report, including to:

prioritise research on sudden unexpected and unexplained deaths of children over 1 year of age to identify potentially modifiable factors so professionals can work to prevent these deaths (see page 8 of the NCMD report, PDF).

The government was asked in January 2026 about the steps it was taking to increase research into SUDC. It replied that the Department of Health and Social Care funds research into SUDC through the National Institute for Health and Care Research (NIHR) and noted the following studies:

Recent NIHR‑funded research includes studies focused on the promotion of safer sleeping practices for families at increased risk, the identification and management of genetic and cardiac risk factors, and the improvement of support for bereaved families. The NIHR actively encourages and funds high-quality research into SUDC, ensuring flexibility in both the funding and research type to meet the needs of patients and families.

SUDC was also debated in Westminster Hall in January 2023.

Parliamentary material on SUDC can be searched via the ‘search parliamentary material’ tool.

Number of sudden unexplained deaths in childhood

Data from the Office for National Statistics’ Nomis Mortality Statistics shows that between 2013 and 2024 there were 205 deaths of children aged one to 19 in England and Wales where the underlying cause was “Other sudden death, cause unknown” (ICD-10 code R96). 108 of these were among children aged one to four years.

As noted above, the National Child Mortality Database (NCMD) has analysed the deaths of all children in England who died suddenly and unexpectedly after birth and before their eighteenth birthday in the period 1 April 2019 to 31 March 2021. Its findings were presented in its report on Sudden and Unexpected Deaths in Infancy and Childhood. It found that there were:

523 sudden and unexpected deaths of children across the two-year period where there was no immediately apparent cause, a rate of 2.28 deaths per 100,000 1-17 year olds. Death rates were highest among the 1–4 year olds (3.46 per 100,000 population) and the 15-17 year olds (3.02 per 100,000 population) (see page 32 of the NCMD report, PDF).

Table 11, on page 33 of the report, provides further information on age at death, sex, area (rural/urban), deprivation and region. The report also provides information on the ‘birth characteristics of the children’ as well as the ‘social environment background of the children’.

Statistics on Unexplained deaths in infancy, in England and Wales are published by the Office for National Statistics (ONS). The most recent data was published in October 2025 and covers the year 2023.

The ONS also publishes data on Child and infant mortality in England and Wales.

Guidance for care and investigation after a child dies

The Royal College of Pathologists published Sudden unexpected death in infancy and childhood: Multi-agency guidelines for care and investigation in 2016. The report is aimed at professions involved in the examination of sudden unexpected death of a child and outlines best practice for each part of the investigation process. The agencies involved can include hospitals, police, children’s social care and the coroner’s office.

The guidance was developed by a working group convened by the Royal College of Pathologists and endorsed by the Royal College of Paediatrics and Child Health (RCPCH).

The RCPCH noted that the original guidelines were published in 2004 and followed high profile cases of miscarriages of justice involving the prosecution of mothers for causing the deaths of their babies. It added that these events:

raised serious concerns about the role of the expert witness in court, issues about standards of proof, the quality of evidence and about the procedures adopted for the investigation of sudden unexpected deaths of infants.

In October 2017, the government published statutory Child Death Review Guidance which aims to standardise practice nationally and enable thematic learning to prevent future deaths. Specifically, it stated that the guidance provides:

[…] a framework for NHS Trusts and Foundation Trusts [for] identifying, reporting, investigating and learning from deaths of inpatients. It requires trusts to collect and publish quarterly information on deaths in their care, reviews, investigations and resulting quality improvement.

The guidance makes clear that a multi-agency approach (covering professionals working in health services, children’s social care services, police, coronial services, education and public health) is key to the effective investigation of an unexpected death, and to support families.

The government also published Child Death Review, Statutory and Operational Guidance (England) in autumn 2018. The document sets out the “key features of what a good child death review process should look like” and that the process combines best practice with statutory requirements that must be followed”.

In February 2026, the charity Child Bereavement UK published a report on Supporting family involvement with the Child Death Review Process. It called for improved communication and support to bereaved families through the standardisation of roles and training for keyworkers assigned to families.

Support for parents and carers

There is no specific support available for sudden unexplained death in childhood. The NHS has published a webpage on sudden infant death syndrome that includes information for parents and carers about how to reduce the risk of it, and bereavement support.

Bereavement support for parents and carers is commissioned locally to meet local needs by integrated care boards and local authorities.

The National Institute for Health and Care Excellence (NICE) published a quality standard (QS160) in 2017 that parents or carers of infants, children and young people are offered support for grief and loss when their child is nearing the end of their life and after their death.

NICE also published guidelines in 2016 and updated in 2019 on End of life care for infants, children and young people with life-limiting conditions: planning and management (NG61). Section 1.4 of the guidelines covers what bereavement care and support local health and social care providers should offer to parents and carers. The NICE quality standards and guidelines also apply to children who die of sudden unexplained deaths.

There are several organisations that provide bereavement support including:

• Cruse Bereavement Support Coping with the death of a child
• The Childhood Bereavement Network org.uk
• Child Bereavement UK org
• A Child of Mineorg.uk
• At A Loss.orgorg
• The Good Grief Trustorg

The Ministry of Justice has published A Guide to Coroner Services for Bereaved People (PDF). This also provides a list of organisations providing support to parents bereaved by the loss of a child.

The charity SUDC UK provides support to families after sudden child loss.