A new study suggests that placental abnormalities during pregnancy may be linked to the risk of sudden infant death syndrome (SIDS) -- the unexpected and sudden death of an apparently healthy infant. Researchers at the Kaiser Foundation Research Institute in Oakland, California, analyzed data from the birth and death certificates of more than 2,000 babies who died of SIDS between 1989 and 1991 and found that two placenta abnormalities, placental abruption and placenta previa, appeared to double a baby's risk for SIDS. Placenta abruption, separation of the placenta prior to birth, and placenta previa, implantation of the placenta in the uterus, can disrupt the normal delivery of oxygen and nutrients to the fetus. Authors suggest the disruptions may effect development of the central nervous system. The study is in the American Journal of Epidemiology (1999; 149:608-611).