Introduction

This chapter aims to provide an increased awareness and understanding of sudden infant death syndrome (SIDS) and to consider the risk factors associated with SIDS, to advise professionals and parents on minimizing risk and to enable parents to be better informed.

Sudden infant death syndrome is defined as the sudden unexpected death of a previously apparently healthy infant within the first year of life. The cause of death is frequently referred to as unexplained or unascertainable following a thorough postmortem examination. All unexpected deaths in infancy are subject to an autopsy, and where a previously undiagnosed underlying problem is found, these cases are no longer reported as SIDS (Foundation for the Study of Infant Deaths [FSID] 2009).

This chapter will address the variable terminology related to SIDS, its incidence, associated risk factors and measures to reduce the incidence, alongside national and international campaigns. In addition, the role of the midwife, health professionals and others will be considered.

Terminology

Sudden infant death syndrome is sometimes referred to as sudden unexplained death in infancy or cot death. Cot death is a term frequently used by parents and the media as it reflects the fact that the death usually occurs during sleep. The term sudden infant death syndrome was brought into common usage in the late 1960s to help bereaved parents and others to ascertain that the death was as a result of an unexplained or unintentional incident; to demonstrate that the parents were not considered to be blamed for the death (Gornall 2008). A diagnosis of SIDS is reached when causes of death are excluded following postmortem examination.

Incidence

The launch of the FSID ‘Back to Sleep’ campaign in 1991 saw a significant reduction in the number of SIDS cases reported (Fleming et al 2006, FSID 2007, Moon et al 2007). Sudden infant death syndrome was already in decline from 1989; nonetheless, the most significant reduction in the rate was in 1992, demonstrating the success of the ‘Reduce the risk’ campaign which encouraged parents and carers to lie babies on their back when going to sleep (FSID 2007). However, there are variations within the rates both within the UK and globally. Moon et al (2007) highlight that SIDS is the leading cause of infant mortality in the developed world. Japan and the Netherlands have the lowest rates at 0.09 and 0.1 per 1000 live births, respectively, and New Zealand has the highest rate at 0.8 per 1000 live births. Following the ‘Back to Sleep’ campaign, data collected and analysed for 2005 identified a decline in SIDS incidents in the UK, with a rate of 0.42 per 1000 live births (FSID 2009). There are variations in the figures across the UK, which may be due to a lack of uniformity in data collection. Whilst the figures continue to demonstrate a decline in SIDS across the UK, an estimated 300 babies a year will die.

Sudden infant death occurs most commonly within the first 4 to 8 weeks of life, and boys are more likely to die than girls, at a ratio of 60:40 (Moon et al 2007); previous data collection in the UK had put the peak of SIDS at 3 months (CEMACH 2008).

SIDS is multifactorial and a number of recommendations are made to advise parents and health professionals of the associated risk factors, to enable interventions to bring about continued decline in the rates.