Dierker L J, Pillay S K, Sorokin Y, Rosen M G
Obstet Gynecol. 1982 Jul;60(1):65-70.
Heart rate variability and fetal movement were used to classify active and quiet fetal periods. Fetuses at 28 to 30 weeks and at 38 to 40 weeks' gestation were compared. A period of fetal movement with increased variability of heart beat was classified as active and one with the absence of movement and diminished fetal heart beat was classified as quiet. The results demonstrated significant differences both in the number of active-quiet cycles per hour and in the length of the active periods. These findings suggest that analogs of fetal behavioral states may be present before birth and have cyclic patterns, and that the time spent in each fetal period is longer in older fetuses.
心率变异性和胎动被用于对胎儿的活跃期和安静期进行分类。对妊娠28至30周以及38至40周的胎儿进行了比较。胎动时心跳变异性增加的时期被归类为活跃期，而无胎动且胎儿心跳减弱的时期被归类为安静期。结果表明，每小时的活跃-安静周期数量以及活跃期的时长均存在显著差异。这些发现表明，胎儿行为状态的类似物可能在出生前就已存在且具有周期性模式，并且在较大胎儿中，每个胎儿期所花费的时间更长。
