Williams T H, Michell R C, Letchworth A T, Noble A D
Lancet. 1977 Dec 3;2(8049):1169-71. doi: 10.1016/s0140-6736(77)91553-7.
Ultrasound examination was done on 442 women early in pregnancy. If there was a discrepancy the date of delivery calculated from ultrasound readings was preferred to that calculated by traditional means. As a result of this policy induction for planned caesarean section was postponed or cancelled in 10.4% of cases. In 9.7% of women the menstrual history was unreliable and the ultrasound measurement was used to estimate the date of delivery. Thus in 21.1% of pregnancies the early ultrasound measurement decided when or whether labour was to be induced. In women induced for postmaturity there was no increase in prolonged labour or need for caesarean section. There were no cases of neonatal respiratory distress and neonatal jaundice was less common than it was when the onset of labour was spontaneous. This evidence suggests that neonatal jaundice is not caused by induction of labour or by the agents used. The low frequency of jaundice in this series is thought to be due to accurate prediction of the expected date of delivery and consequent exclusion of premature babies born to "postmature" women.
对442名孕妇在妊娠早期进行了超声检查。如果存在差异，根据超声读数计算的分娩日期优先于传统方法计算的日期。由于这一政策，计划剖宫产的引产在10.4%的病例中被推迟或取消。在9.7%的女性中，月经史不可靠，超声测量被用于估计分娩日期。因此，在21.1%的妊娠中，早期超声测量决定了何时或是否引产。在因过期妊娠而引产的女性中，产程延长或剖宫产需求没有增加。没有新生儿呼吸窘迫病例，新生儿黄疸比自然发动分娩时少见。这一证据表明，新生儿黄疸不是由引产或所用药物引起的。该系列中黄疸发生率低被认为是由于准确预测了预期分娩日期，从而排除了“过期妊娠”女性所生的早产儿。
