Dawes G S, Houghton C R, Redman C W, Visser G H
Br J Obstet Gynaecol. 1982 Apr;89(4):276-84. doi: 10.1111/j.1471-0528.1982.tb04696.x.
With an improved method for fitting baselines to human fetal heart-rate traces, the patterns of episodic variations, accelerations and decelerations were similar in 215 64-min records from normal pregnancies and in 95 with mild hypertension and normal outcome. The change in signal loss with gestational age, by Doppler ultrasound for recording heart rate, was entirely due to the greater loss in episodes of high heart-rate variation. The changes in the numbers and sizes of accelerations and decelerations with gestational age were described. There were many records which had only one or no acceleration at 28-33 weeks gestation (16.2%) or 34-41 weeks (7.3%). However, only two (0.7%) had episodes of high heart-rate variation lasting less than 10 min from 28 weeks onwards. The presence of these episodes, with clusters of fetal movements, is therefore likely to be a better numerical index of normality.
采用一种改进的方法对人类胎儿心率轨迹进行基线拟合，在215份来自正常妊娠的64分钟记录以及95份患有轻度高血压且结局正常的记录中，发作性变化、加速和减速的模式相似。通过多普勒超声记录心率时，信号丢失随孕周的变化完全是由于高心率变化发作时的更大丢失。描述了加速和减速的数量及大小随孕周的变化。有许多记录在妊娠28 - 33周（16.2%）或34 - 41周（7.3%）时只有一次或没有加速。然而，从28周起，只有两份记录（0.7%）有持续时间少于10分钟的高心率变化发作。因此，这些伴有胎儿运动簇的发作的存在可能是更好的正常性数值指标。
