[Epidemiology and morphology of sudden death in infancy in twins and siblings].

429 SIDS cases were investigated in a retrospective study. For this study, the deaths in which at least one brother or sister had died under comparable circumstances were evaluated. The 429 babies who had died comprised 17 multiple birth babies (3.7%) including 15 twin and two triplet babies. Eleven cases (2.6%) were brothers or sisters of SIDS victims. In three cases, relatives of the baby's mother had died of sudden infant death. A comparison of the various case groups did not reveal any patho-morphologically significant differences between the groups or differences from other SIDS cases. All the multiple birth babies were immature and premature babies. There was a raised incidence of poor socio-economic conditions in the sibling group. The results are significant for parent counselling, any preventive measures and the detection of concurrent (in particular, unnatural) causes of death.