Smith C V, Phelan J P, Paul R H
Am J Obstet Gynecol. 1985 Dec 1;153(7):780-2. doi: 10.1016/0002-9378(85)90346-1.
The nonstress test is of recognized value for the antepartum assessment of fetal well-being. Less well defined, however, is the relationship between baseline fetal heart rate, reactivity, and the gestational age of the fetus. A prospective analysis of the nonstress test in a preterm, low-risk population was begun. Weekly tests were begun as early as 23 weeks and continued to term. A test was considered reactive if there were two or more fetal heart rate accelerations within a 20-minute period. A total of 128 nonstress tests were performed on 25 low-risk patients. Of these tests, 84 (64%) were considered reactive. With advancing gestational age, a progressive increase in the incidence of reactive tests was observed. However, no significant difference in baseline fetal heart rate could be identified between term and preterm fetuses. In addition, the frequency and amount of accelerations and decelerations were determined. Decelerations were not noted more frequently in the preterm population. Conversely, accelerations occurred more frequently with advancing gestational age. The pregnancy outcome was excellent for all study patients. It is concluded, therefore, that with advancing gestational age more reactive nonstress tests are seen. Baseline fetal heart rate and the frequency of decelerations appear to be unaffected by advancing gestational age. Finally, although the numbers are small, the nonstress test appears to be a suitable technique for assessing fetal well-being in the preterm fetus.
无应激试验对于产前评估胎儿健康状况具有公认的价值。然而，胎儿基线心率、反应性与胎儿孕周之间的关系却不太明确。于是对早产低风险人群进行了无应激试验的前瞻性分析。早在孕23周开始每周进行测试，持续至足月。如果在20分钟内有两次或更多次胎儿心率加速，则该测试被认为是有反应性的。对25名低风险患者共进行了128次无应激试验。其中84次（64%）测试被认为是有反应性的。随着孕周增加，有反应性测试的发生率逐渐上升。然而，足月胎儿与早产胎儿的基线心率并无显著差异。此外，还确定了加速和减速的频率及幅度。早产人群中减速情况并未更频繁出现。相反，随着孕周增加，加速情况更频繁出现。所有研究患者的妊娠结局都很好。因此得出结论，随着孕周增加，会出现更多有反应性的无应激试验。基线胎儿心率和减速频率似乎不受孕周增加的影响。最后，尽管样本数量较少，但无应激试验似乎是评估早产胎儿健康状况的一种合适技术。
