The factors contributing to the risk of sudden infant death syndrome.

Sudden infant death syndrome (SIDS) is defined as the sudden death of an infant under one year of age which remains unexplained after a thorough case investigation, including performance of a complete autopsy, examination of the death scene and review of the clinical history. SIDS is one of the leading causes of infant mortality and occurs from the first month, until the first year of life for newborns and infants.The aim of this review was to identify and examine risk factors responsible for causing the sudden infant death and to propose certain measures in order to protect newborns and infants from sudden death. The potential factors that contribute to the occurrence of SIDS include inadequate prenatal care, low birth weight (<2499gr), premature infants, intrauterine growth delay, short interval between pregnancies and maternal substance use (tobacco, alcohol, opiates). Moreover, factors related to infant's sleep environment such as the prone or side sleeping position and thick coverlet increase the risk of sudden death in infants. Also, the combination of risk factors such as that of prone sleeping position and soft bed mattress are linked to a 20-fold increased risk of death. Finally, polymorphisms in the serotonin transporter gene (5-HTT), viral respiratory infections, long Q-T (responsible for the presence of fatal arrhythmia) are related to the SIDS.Literature review indicates that each individual risk factor contributes to the appearance of SIDS and the establishment of certain protective measures for parents and health professionals has reduced its prevalence. But the precise identification of the SIDS causes and how these contribute to the occurrence of sudden death in neonates and infants, remains a challenge for health professionals.