P, a nineteen-year-old woman, gave birth to a healthy baby, Justice Eugene Falcon, in the early morning hours of March 21, 1973. Moments after delivery, P coughed, gagged, convulsed, became cyanotic, and suffered a complete respiratory and cardiac collapse. Attempts to revive her were unsuccessful. She was pronounced dead soon thereafter. The autopsy report indicated that amniotic fluid embolism, an unpreventable complication that occurs in approximately one out of ten or twenty thousand births, was the cause of death. The survival rate of amniotic fluid embolism is, according to P's expert witness, 37.5 percent if an intravenous line is connected to the patient before the onset of the embolism. In this case, an intravenous line had not been established. The trial court dismissed the complaint because the evidence did not show that P probably -- defined as more than fifty percent -- would have survived if the procedure had not been omitted. The Court of Appeals reversed, stating that P need only 'establish that the omitted treatment or procedure had the potential for improving the patient's recovery or preventing the patient's death.' The Court added that 'while a plaintiff must show some probability that the treatment would be successful, that probability need not be greater than fifty percent.' D appealed.