A woman in labor and not wearing a seat belt sustained multiple fractures of the pelvis and femur while in an automobile accident. The fetus suffered fractures of the parietal and occipital bones. To minimize maternal pelvic and fetal injury, delivery by cesarean section was performed. The infant had generalized cerebral edema and intraventricular and subarachnoid hemorrhage, diagnosed shortly after birth. Motor abnormalities and residual injury to the periventricular white matter were evident at age 4 months. Use of seat belts may significantly diminish or prevent such injuries.