The purpose of this study was to determine the risk factors predisposing to an obstetric fracture, and their long-term outcome. We reviewed 28 obstetric fractures treated in the County of Vaud, Switzerland, between 1976 and 1989. There were 12 fractures of long bones, 10 clavicles and 6 depressed skull fractures. The belief that obstetric fractures occur in large babies or after breech deliveries is no longer valid. The common risk factors of these fractures are obstetric maneuvers during delivery (75% of cases), especially Cesarean sections (35%), prolonged labor (33%), and prematurity (25%). Cephalic presentation (64.2% of cases) is more frequent than breech position (32.1%). Weight, size, age of gestation, age of the mother, parity, gestity, and time of delivery cannot be considered as risk factors for obstetric fractures. For each type of fracture some specific risk factors are pointed out: maneuvers at birth for depressed skull fracture, Cesarean section, breech delivery with assistance and low birth weight for the fractures of long bones. All fractures were treated conservatively, except for skull fractures with a depression of more than 2 cm. Early consolidation is achieved within 2 weeks. Long-term prognosis for obstetric fractures is good without sequelae.