In a prospective study, late obstetric complications were common, one or more occurring in 62% of 51,285 pregnancies. We examined these complications as risk factors for cerebral palsy (CP) or nonfebrile seizure disorders. Certain complications were associated with an increased rate of CP, but in babies over 2,500 g, the observed rate of CP did not exceed 2% following any condition evaluated. For most conditions, the CP rate was highest in the small subgroup of children who had five-minute Apgar scores of 3 or less. Most babies over 2,500 g born after each complication achieved five-minute Apgar scores of 7 or higher, and for them the risk of CP was not significantly greater than in children whose births were uncomplicated. Neither the complications considered nor Apgar scores were important antecedents of nonfebrile seizure disorders in children free of CP.