"Justice O'Connor, ten years after Roe, described the trimester approach as "on a collision course with itself." Advances in medical technology would continue to move forward the point at which regulation could be justified as protective of a woman's health, and to move backward the point of viability, when the state could proscribe abortions unnecessary to preserve the patient's life or health. The approach, she thought, impelled legislatures to remain aucourant with changing medical practices and called upon courts to examine legislative judgments, not as jurists applying "neutral principles," but as "science review boards.""