Risk Factors for Sudden Infant Death Syndrome: An Updated Narrative Review

Abstract

Background: Sudden Infant Death Syndrome (SIDS) is defined as the sudden and unexplained death of an infant younger than one year of age that remains unexplained after a comprehensive investigation, including autopsy, examination of the death scene, and review of clinical and family history. Despite a substantial reduction in incidence following the implementation of safe sleep recommendations, SIDS remains an important public health concern. Multiple maternal, infant-related, environmental, and socioeconomic factors contribute to SIDS risk.

Objective: The aim of this narrative review was to summarize current evidence regarding modifiable and non-modifiable risk factors associated with Sudden Infant Death Syndrome and to discuss evidence-based preventive strategies.

Methods: A narrative review of literature from PubMed/MEDLINE, Scopus, Web of Science, and Embase was conducted, including reviews, meta-analyses, observational studies, and clinical guidelines.

Results: Current evidence indicates that SIDS is a multifactorial condition resulting from interactions between intrinsic infant vulnerability, developmental factors, and external environmental stressors. The strongest modifiable risk factors include prenatal and postnatal tobacco exposure, prone sleeping position, unsafe sleep environments, overheating, and bed-sharing in high-risk circumstances. Prematurity, low birth weight, male sex, and genetic susceptibility contribute to biological vulnerability. Breastfeeding and pacifier use during sleep are associated with reduced SIDS risk.

Conclusions: SIDS prevention requires a multifactorial approach focused on reducing modifiable environmental risks, promoting safe sleep practices, eliminating tobacco exposure, and improving parental education. Further research is needed to better understand genetic and biological mechanisms contributing to individual susceptibility.