Abstract：
BACKGROUND: There is a growing body of evidence that the presence and length of the purple line could represent a non-invasive method of estimating and determining labour progress.
OBJECTIVE: The primary outcome was to provide a systematic review and meta-analysis on the association between the purple line length and cervical dilatation in active labour. The secondary outcome was to determine the association between the purple line length and the fetal head descent, and to calculate the pooled mean length of the purple line at a cervical dilatation of 3-4 cm and at a cervical dilatation of 9-10 cm.
METHODS: We searched the Medline, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), Clinical Trials.gov and Cochrane Pregnancy and Childbirth\'s Trials Register databases from inception till March 25, 2023.
METHODS: We included observational studies of pregnant women in active first stage of labour who had their labour progress assessed with the use of regular vaginal examinations and who had the occurrence recorded and length of the purple line measured at the same time.
METHODS: Two reviewers independently evaluated study eligibility. We used the random effects and fixed effects model for meta-analysis.
RESULTS: There were six eligible studies included in the systematic review that reported on 982 women in total with the purple line appearing in 760 (77.3%) of cases. We found a moderate positive pooled correlation between the purple line length with cervical dilatation (r = +0.64; 95%CI: 0.41-0.87) and fetal head descent (r = +0.50; 95%CI: 0.32-0.68). For women either in spontaneous or induced labour, the pooled mean length of the purple line was more than 9.4 cm when the cervical dilatation was 9-10 cm, whereas it was more than 7.3 cm when the cervical dilatation was 3-4 cm.
CONCLUSIONS: The purple line is a non-invasive method that may potentially be used as an adjunct in labour progress assessment.
OBJECTIVE: The primary outcome was to provide a systematic review and meta-analysis on the association between the purple line length and cervical dilatation in active labour. The secondary outcome was to determine the association between the purple line length and the fetal head descent, and to calculate the pooled mean length of the purple line at a cervical dilatation of 3-4 cm and at a cervical dilatation of 9-10 cm.
METHODS: We searched the Medline, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), Clinical Trials.gov and Cochrane Pregnancy and Childbirth\'s Trials Register databases from inception till March 25, 2023.
METHODS: We included observational studies of pregnant women in active first stage of labour who had their labour progress assessed with the use of regular vaginal examinations and who had the occurrence recorded and length of the purple line measured at the same time.
METHODS: Two reviewers independently evaluated study eligibility. We used the random effects and fixed effects model for meta-analysis.
RESULTS: There were six eligible studies included in the systematic review that reported on 982 women in total with the purple line appearing in 760 (77.3%) of cases. We found a moderate positive pooled correlation between the purple line length with cervical dilatation (r = +0.64; 95%CI: 0.41-0.87) and fetal head descent (r = +0.50; 95%CI: 0.32-0.68). For women either in spontaneous or induced labour, the pooled mean length of the purple line was more than 9.4 cm when the cervical dilatation was 9-10 cm, whereas it was more than 7.3 cm when the cervical dilatation was 3-4 cm.
CONCLUSIONS: The purple line is a non-invasive method that may potentially be used as an adjunct in labour progress assessment.
摘要：
背景：越来越多的证据表明，紫色线的存在和长度可以代表一种评估和确定分娩进度的非侵入性方法。
目的：主要结局是对积极分娩中紫线长度与宫颈扩张之间的关系进行系统评价和荟萃分析。次要结局是确定紫线长度与胎儿头部下降之间的关联，并计算在宫颈扩张3-4厘米和宫颈扩张9-10厘米时紫色线的合并平均长度。
方法：我们搜索了Medline，Scopus,Cochrane中央对照试验登记册（中央），临床试验.gov和Cochrane怀孕和分娩试验注册数据库从开始到2023年3月25日。
方法：我们纳入了对处于第一产程中的孕妇的观察性研究，这些孕妇通过定期的阴道检查评估了其产程进展，并记录了发生并同时测量了紫线的长度。
方法：两名评审员独立评估研究资格。我们使用随机效应和固定效应模型进行荟萃分析。
结果：系统评价中纳入了6项符合条件的研究，共报道了982名女性，其中760例（77.3%）出现紫色线。我们发现紫线长度与宫颈扩张（r=0.64；95CI：0.41-0.87）和胎儿头部下降（r=0.50；95CI：0.32-0.68）之间存在中度正相关。对于自然分娩或引产的妇女，当宫颈扩张为9-10厘米时，紫色线的合并平均长度超过9.4厘米，而宫颈扩张3-4厘米时超过7.3厘米。
结论：紫线是一种非侵入性方法，可能用作分娩进展评估的辅助手段。
目的：主要结局是对积极分娩中紫线长度与宫颈扩张之间的关系进行系统评价和荟萃分析。次要结局是确定紫线长度与胎儿头部下降之间的关联，并计算在宫颈扩张3-4厘米和宫颈扩张9-10厘米时紫色线的合并平均长度。
方法：我们搜索了Medline，Scopus,Cochrane中央对照试验登记册（中央），临床试验.gov和Cochrane怀孕和分娩试验注册数据库从开始到2023年3月25日。
方法：我们纳入了对处于第一产程中的孕妇的观察性研究，这些孕妇通过定期的阴道检查评估了其产程进展，并记录了发生并同时测量了紫线的长度。
方法：两名评审员独立评估研究资格。我们使用随机效应和固定效应模型进行荟萃分析。
结果：系统评价中纳入了6项符合条件的研究，共报道了982名女性，其中760例（77.3%）出现紫色线。我们发现紫线长度与宫颈扩张（r=0.64；95CI：0.41-0.87）和胎儿头部下降（r=0.50；95CI：0.32-0.68）之间存在中度正相关。对于自然分娩或引产的妇女，当宫颈扩张为9-10厘米时，紫色线的合并平均长度超过9.4厘米，而宫颈扩张3-4厘米时超过7.3厘米。
结论：紫线是一种非侵入性方法，可能用作分娩进展评估的辅助手段。
