ArticleBMC pregnancy and childbirth2010
The purple line as a measure of labour progress: a longitudinal study.
Article in BMC pregnancy and childbirth, 2010. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 2 of them syntheses that pooled it.
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Who cites it
13 citing papers in PubMed, 2 syntheses or guidelines pooled it, 35 citations in OpenAlex.
- Accuracy of non-invasive methods for assessing the progress of labor in the first stage: a systematic review and meta-analysis.BMC pregnancy and childbirth · 2022Pooled it
- Routine vaginal examinations compared to other methods for assessing progress of labour to improve outcomes for women and babies at term.The Cochrane database of systematic reviews · 2022Pooled it
- The success of vaginal birth by use of trans-labial ultrasound plus vaginal examination and vaginal examination only in pregnant women with labor induction: a comparative study.BMC pregnancy and childbirth · 2023Trial
- Mapping Intrusive and Non-Intrusive Ultrasound Technologies and Devices Used in Vaginal Examinations During Intrapartum: A Scoping Review.Healthcare (Basel, Switzerland) · 2026Review
- Balancing safety and comfort in childbirth: a grounded theory of labor progress assessment among frontline obstetric healthcare providers.BMC nursing · 2026Article
- Alternative approach to monitoring labor: purple line.BMC pregnancy and childbirth · 2025Observational
- Methods to reduce the number of vaginal examinations in labour progress assessment so as to support normality at childbirth.Archives of gynecology and obstetrics · 2024Article
- Normal childbirth: The natural, non-medical, alternative approaches to the most common medical interventions in labor.European journal of midwifery · 2023Article
- Development and validation of a predictive model to identify the active phase of labor.BMC pregnancy and childbirth · 2022Article
- Vaginal Examinations During Childbirth: Consent, Coercion and COVID-19.Feminist legal studies · 2021Article
- Cervical Evaluation: From Ancient Medicine to Precision Medicine.Obstetrics and gynecology · 2017Article
- The diagnostic accuracy of purple line in prediction of labor progress in omolbanin hospital, iran.Iranian Red Crescent medical journal · 2014Article
- Improving vaginal examinations performed by midwives.Sultan Qaboos University medical journal · 2013Article
Corrections and comments
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Authors and funding
6 authors at 1 institution in 1 country.
Funding
Abstract
backgroundVaginal examination (VE) and assessment of the cervix is currently considered to be the gold standard for assessment of labour progress. It is however inherently imprecise with studies indicating an overall accuracy for determining the diameter of the cervix at between 48-56%. Furthermore, VEs can be unpleasant, intrusive and embarrassing for women, and are associated with the risk of introducing infection. In light of increasing concern world wide about the use of routine interventions in labour it may be time to consider alternative, less intrusive means of assessing progress in labour. The presence of a purple line during labour, seen to rise from the anal margin and extend between the buttocks as labour progresses has been reported. The study described in this paper aimed to assess in what percentage of women in labour a purple line was present, clear and measurable and to determine if any relationship existed between the length of the purple line and cervical dilatation and/or station of the fetal head.
methodsThis longitudinal study observed 144 women either in spontaneous labour (n = 112) or for induction of labour (n = 32) from admission through to final VE. Women were examined in the lateral position and midwives recorded the presence or absence of the line throughout labour immediately before each VE. Where present, the length of the line was measured using a disposable tape measure. Within subjects correlation, chi-squared test for independence, and independent samples t-test were used to analyse the data.
resultsThe purple line was seen at some point in labour for 109 women (76%). There was a medium positive correlation between length of the purple line and cervical dilatation (r = +0.36, n = 66, P = 0.0001) and station of the fetal head (r = +0.42, n = 56, P < 0.0001).
conclusionsThe purple line does exist and there is a medium positive correlation between its length and both cervical dilatation and station of the fetal head. Where the line is present, it may provide a useful guide for clinicians of labour progress along side other measures. Further research is required to assess whether measurement of the line is acceptable to women in labour and also clinicians.
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