ArticleAmerican journal of obstetrics and gynecology2002
Reassessing the labor curve in nulliparous women.
Article in American journal of obstetrics and gynecology, 2002. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 2 registered trials, which are not on this map. Cited by 77 papers, 5 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Intrapartum Ultrasonography - Sonopartogram. Longitudinal Evaluation of the Mechanism of Active Labor Using Ultrasound Parameters
Impact of Low-Dose Epidural Analgesia on Labour Progression in Robson Class 1 Women: a Retrospective Study
Who cites it
77 citing papers in PubMed, 5 syntheses or guidelines pooled it.
- Influence of Maternal Obesity on Labor Induction: A Systematic Review and Meta-Analysis.Journal of midwifery & women's health · 2019Pooled it
- Cervical dilatation patterns of 'low-risk' women with spontaneous labour and normal perinatal outcomes: a systematic review.BJOG : an international journal of obstetrics and gynaecology · 2018Pooled it
- Duration of spontaneous labour in 'low-risk' women with 'normal' perinatal outcomes: A systematic review.European journal of obstetrics, gynecology, and reproductive biology · 2018Pooled it
- Diagnosing onset of labor: a systematic review of definitions in the research literature.BMC pregnancy and childbirth · 2016Pooled it
- "Active labor" duration and dilation rates among low-risk, nulliparous women with spontaneous labor onset: a systematic review.Journal of midwifery & women's healthPooled it
- The effect of Zhang's guideline vs the WHO partograph on childbirth experience measured by the Childbirth Experience Questionnaire in the Labor Progression Study (LaPS): A cluster randomized trial.Acta obstetricia et gynecologica Scandinavica · 2022Trial
- Induction of labor compared to expectant management in term nulliparas with a latent phase of labor of more than 8 hours: a randomized trial.BMC pregnancy and childbirth · 2019Trial
- Study protocol: the Labor Progression Study, LAPS - does the use of a dynamic progression guideline in labor reduce the rate of intrapartum cesarean sections in nulliparous women? A multicenter, cluster randomized trial in Norway.BMC pregnancy and childbirth · 2017Trial
- Foley catheter for induction of labor: potential barriers to adopting the technique.Journal of perinatology : official journal of the California Perinatal Association · 2015Trial
- Impact of active phase duration on neonatal and maternal adverse outcomes: A systematic analysis of parity stratification, body mass index interaction, and predictive modeling in a retrospective cohort.International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics · 2026Article
- An Appraisal of Labor Augmentation: An Update on Current Evidence and Practice.Maternal-fetal medicine (Wolters Kluwer Health, Inc.) · 2026Review
- Body mass index and failed induction of labor: A cohort study.Acta obstetricia et gynecologica Scandinavica · 2025Article
- Article
- Comparison of Two Low-Dose Regimens of Intravenous Fentanyl for Pain Relief During Labor: A Double-Blind Randomized Controlled Trial.Healthcare (Basel, Switzerland) · 2025Article
- Ultrasonographic Evaluation of Labor Patterns: A Prospective Cohort Study in Greece.Journal of clinical medicine · 2025Article
- Development and preliminary validation of the GebStart-tool for advising nulliparous women in early labour.PloS one · 2025Article
- Mode of delivery may seriously affect omics studies using umbilical cord blood and amniotic fluid.Archives of gynecology and obstetrics · 2024Article
- Inconsistent definitions of prolonged labor in international literature: a scoping review.AJOG global reports · 2024Article
- New labor curves of dilation and station to improve the accuracy of predicting labor progress.American journal of obstetrics and gynecology · 2024Article
- Ultrasonographic Evaluation of the Second Stage of Labor according to the Mode of Delivery: A Prospective Study in Greece.Journal of clinical medicine · 2024Article
17 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
3 authors.
Funding
Abstract
objectivesOur purpose was to examine the pattern of labor progression in nulliparous parturients in contemporary obstetric practice. STUDY
designWe extracted detailed labor data from 1329 nulliparous parturients with a term, singleton, vertex fetus of normal birth weight after spontaneous onset of labor. Cesarean deliveries were excluded. We used a repeated-measures regression with a 10th-order polynomial function to discover the average labor curve under contemporary practice. With use of an interval-censored regression with a log normal distribution, we also computed the expected time interval of the cervix to reach the next centimeter, the expected rate of cervical dilation at each phase of labor, and the duration of labor for fetal descent at various stations.
resultsOur average labor curve differs markedly from the Friedman curve. The cervix dilated substantially slower in the active phase. It took approximately 5.5 hours from 4 cm to 10 cm, compared with 2.5 hours under the Friedman curve. We observed no deceleration phase. Before 7 cm, no perceivable change in cervical dilation for more than 2 hour was not uncommon. The 5th percentiles of rate of cervical dilation were all below 1 cm per hour. The 95th percentile of time interval for fetal descent from station +1/3 to +2/3 was 3 hours at the second stage.
conclusionOur results suggest that the pattern of labor progression in contemporary practice differs significantly from the Friedman curve. The diagnostic criteria for protraction and arrest disorders of labor may be too stringent in nulliparous women.
Indexed as
Identifiers
12388957What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.