Objective This paper is to investigate the ratio of the systolic peak value and the end-diastolic velocity of blood flow (S/D value) and its clinical value, which can predict fetal anoxia.

• 目的探讨脐动脉收缩期血流峰值(S)与舒张末期血流速度(D)的比值(S/D)对预测胎儿宫内缺氧的临床价值。