用193例正常胎儿尸体观察测量了脊髓的全长、重量、体积、颈膨大、腰骶膨大及终丝等方面出生前的逐月发育值及位置的变化.在4个月时脊髓已脱离了骶管;出生时脊髓下端位于腰2～腰3椎体间高度;硬脊膜囊下界位于骶1～骶2椎体间高度;外终丝止点基本在尾1～尾2椎体间;脊髓长与身长之比逐月下降.至出生前约为1/3;脊髓重与体重之比始终保持在0.1%左右.脊髓发的性别差异不明显.上述结果可为教学及临床提供基本的参考数据. 193 normal fetuses were used to observe the changes in the monthly development and location of the spinal cord before birth in terms of full-length, weight, volume, neck enlargement, lumbosacral enlargement, and terminal filaments. At 4 months, the spinal cord was detached Sacral tube; at birth, the lower end of the spinal cord is located in the lumbar 2 ~ lumbar 3 interbody height; the dural sac in sacral 1 ~ sacral 2 vertebral body height; The ratio of spinal cord length to body length decreased from month to month, and it was about 1/3 before birth. The ratio of weight to weight of spinal cord remained at about 0.1% .The sex difference of spinal cord was not obvious.The above results could provide basic teaching and clinical Reference data