[经超声测量子宫下段以评估子宫破裂风险]

[Echographic measurement of the inferior uterine segment for assessing the risk of uterine rupture].

作者信息

Rozenberg P, Goffinet F, Philippe H J, Nisand I

机构信息

Service de Gynécologie et Obstétrique, Centre Hospitalier Intercommunal de Poissy.

出版信息

J Gynecol Obstet Biol Reprod (Paris). 1997;26(5):513-9.

PMID:9417464

Abstract

BACKGROUND

Ultrasonography has been used to examine the scarred uterus in women who have had previous cesarean sections in an attempt to assess the risk of rupture of the scar during subsequent labor. The predictive value of such measurements has not been adequately assessed, however. We aimed to evaluate the usefulness of sonographic measurement of the lower uterine segment before labor in predicting the risk of intrapartum uterine rupture.

METHODS

In this prospective observational study, the obstetricians were not told the ultrasonographic findings and did not use them to make decisions about type of delivery. Eligible patients were those with previous cesarean sections booked for delivery at our hospital. 642 patients underwent ultrasound examination at 36-38 weeks' gestation, and were allocated to four groups according to the thickness of the lower uterine segment. Ultrasonographic findings were compared with those of physical examination at delivery.

FINDINGS

The overall frequency of defective scars was 4.0% (15 uterine ruptures and 10 dehiscences). The frequency of defects rose as the thickness of the lower uterine segment decreased: there were no defects among 278 women with measurements greater than 4.5 mm, three (2%) among 177 patients with values of 3.6-4.5 mm, 14 (10%) among 136 patients with values of 2.6-3.5 mm, and eight (16%) among 51 women with values of 1.6-2.5 mm. With a cut-off value of 3.5 mm, the sensitivity of ultrasonographic measurement was 88.0%, the specificity 73.2%, positive predictive value 11.8%, and negative predictive value 99.3%.

INTERPRETATION

Our results show that the risk of a defective scar is directly correlated to the degree of thinning of the lower uterine segment at around 37 weeks of pregnancy. The high negative predictive value of the method may encourage obstetricians in hospitals where routine repeat elective cesarean is the standard procedure to offer a trial of labor to patients with a thickness value of 3.5 mm or greater.

摘要

背景

超声检查已被用于检查有过剖宫产史的女性的瘢痕子宫，以评估其在随后分娩过程中瘢痕破裂的风险。然而，此类测量的预测价值尚未得到充分评估。我们旨在评估临产前超声测量子宫下段在预测产时子宫破裂风险方面的实用性。

方法

在这项前瞻性观察研究中，产科医生未被告知超声检查结果，也未将其用于分娩方式的决策。符合条件的患者为在我院预约分娩的有过剖宫产史的女性。642例患者在妊娠36 - 38周时接受了超声检查，并根据子宫下段厚度分为四组。将超声检查结果与分娩时的体格检查结果进行比较。

结果

瘢痕缺陷的总体发生率为4.0%（15例子宫破裂和10例裂开）。随着子宫下段厚度的减小，缺陷发生率升高：在278例测量值大于4.5 mm的女性中无缺陷，在177例测量值为3.6 - 4.5 mm的患者中有3例（2%），在136例测量值为2.6 - 3.5 mm的患者中有14例（10%），在51例测量值为1.6 - 2.5 mm的女性中有8例（16%）。以3.5 mm为临界值，超声测量的敏感性为88.0%，特异性为73.2%，阳性预测值为11.8%，阴性预测值为99.3%。