Sabbagha R E, Hughey M
Obstet Gynecol. 1978 Oct;52(4):402-6.
At present a large number of different charts are used for prediction of gestational age from sonar biparietal diameter (BPD). In this report the reasons for these observed differences are presented. Additionally, the usefulness of all these charts is questioned because a) the mean differences in 7059 BPDs derived by the B-scan from four large fetal population studies are not significantly different from zero and b) BPDs obtained by B scan are statistically comparable to gray-scale or real-time BPDs if medium gain is used. Thus, it is our suggestion that a chart showing the composite mean BPD values of all four studies be used universally for prediction of fetal age. Finally, the guidelines of using sonar BPD as an index of gestational age are presented and the role of the obstetrician in interpreting BPD data is emphasized.
目前，大量不同的图表被用于根据超声双顶径（BPD）预测孕周。在本报告中，阐述了观察到这些差异的原因。此外，所有这些图表的实用性受到质疑，原因如下：a）来自四项大型胎儿群体研究的B超得出的7059个双顶径的平均差异与零无显著差异；b）如果使用中等增益，B超获得的双顶径在统计学上与灰阶或实时双顶径具有可比性。因此，我们建议普遍使用显示所有四项研究综合平均双顶径值的图表来预测胎儿年龄。最后，给出了将超声双顶径用作孕周指标的指导原则，并强调了产科医生在解释双顶径数据中的作用。
