The results of the research, which are carried out according to two international programs on studying and prevention of the sudden infant death syndrome (SIDS), are submitted in the article. The features of ante- and perinatal periods, characteristics of obstetric history of the mothers of deceased babies are analyzed, the relative risk of SIDS development is estimated at the influence of a complex of factors. High parity, young age of mother at the time of delivery, poor antenatal care, preterm delivery, intrauterine fetal growth retardation, fast delivery, alcohol and coffee abuse by a mother, smoking during pregnancy, early change of the child's feeding from breast to bottle are referred to the most significant risk factors of SIDS stipulated by the unfavorable course of pregnancy and delivery. The practical recommendations directed on elimination of the risk factors of SIDS in ante- and perinatal periods are offered.