Bérubé Laurie, Arial Mariko, Gagnon Geneviève, Brassard Normand, Boutin Amélie, Bujold Emmanuel
Centre de recherche du Centre Hospitalier Universitaire de Québec, Québec QC.
J Obstet Gynaecol Can. 2011 Jun;33(6):581-7. doi: 10.1016/s1701-2163(16)34906-4.
To estimate the association between potential influencing factors and lower uterine segment (LUS) thickness at term in women with previous Caesarean section.
We conducted a cohort study of women with previous low-transverse Caesarean section undergoing ultrasonographic measurement of LUS thickness between 35 and 38 weeks' gestation in a tertiary care centre between 2006 and 2009. Measurements of the full LUS thickness and the myometrial LUS thickness were performed both transabdominally and transvaginally. The thinnest measurements for both full and myometrial LUS thicknesses were considered dependent variables. Non-parametric analyses, multivariate linear regression analyses, and multivariate regression analyses were used to evaluate the relationships between LUS thickness and the potential influencing factors of maternal age, interdelivery interval, prior vaginal delivery, and several characteristics of the previous Caesarean section.
In 377 women who underwent measurement of LUS thickness, labour before previous Caesarean section was the only characteristic associated with a greater full LUS thickness (an additional 0.9 mm; 95% CI 0.5 to 1.2 mm) in multivariate linear regression analysis. Labour before previous Caesarean section (0.5 mm; 95% CI 0.2 to 0.7 mm) and the use of synthetic sutures (as opposed to catgut sutures) for the closure of the previous hysterotomy incision (0.3 mm; 95% CI 0.02 to 0.5 mm) were the only two variables significantly associated with a thicker myometrial LUS. In multivariate regression analysis, three factors were predictive of a full LUS thickness of > 2.3 mm: the presence of labour, a recurrent indication for Caesarean section, and the use of synthetic sutures for hysterotomy closure at previous Caesarean section (P < 0.05).
Labour at the time of previous Caesarean section is associated with a thicker LUS near term in the subsequent pregnancy. The use of synthetic sutures for hysterotomy closure is another factor potentially associated with a thicker LUS.
评估既往有剖宫产史的女性足月时潜在影响因素与子宫下段（LUS）厚度之间的关联。
我们对2006年至2009年在一家三级医疗中心接受超声测量LUS厚度的既往行低位横切口剖宫产的女性进行了一项队列研究。在妊娠35至38周期间经腹和经阴道测量整个LUS厚度和肌层LUS厚度。整个LUS厚度和肌层LUS厚度的最薄测量值被视为因变量。采用非参数分析、多元线性回归分析和多元回归分析来评估LUS厚度与产妇年龄、分娩间隔、既往阴道分娩以及既往剖宫产的几个特征等潜在影响因素之间的关系。
在377名接受LUS厚度测量的女性中，多因素线性回归分析显示，既往剖宫产术前有分娩史是与整个LUS厚度增加相关的唯一特征（增加0.9mm；95%CI 0.5至1.2mm）。既往剖宫产术前有分娩史（0.5mm；95%CI 0.2至0.7mm）以及在既往子宫下段剖宫产切口缝合时使用合成缝线（而非肠线）（0.3mm；95%CI 0.02至0.5mm）是与肌层LUS增厚显著相关的仅有的两个变量。在多因素回归分析中，三个因素可预测整个LUS厚度>2.3mm：有分娩史、剖宫产重复指征以及既往剖宫产时子宫下段剖宫产切口缝合使用合成缝线（P<0.05）。
既往剖宫产时的分娩与后续妊娠近足月时较厚的LUS有关。子宫下段剖宫产切口缝合使用合成缝线是另一个可能与较厚LUS相关的因素。
