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Updated: Jul 6, 2026
08:07
Electromyometrial Imaging of Uterine Contractions in Pregnant Women
Published on: May 26, 2023
[What is the duration of normal labour?]
Ellen Blix1, Merethe Kumle, Pål Øian
1Institutt for klinisk medisin, Universitetet i Tromsø, 9038 Tromsø. eblix@barentsnett.no
Summary
Normal labor duration lacks scientific definition, impacting care for many women experiencing slow labor progress. Systematic recording and further research are crucial for understanding prolonged labor and timely interventions.
Area of Science:
- Obstetrics and Gynecology
- Maternal-Fetal Medicine
- Labor and Delivery Management
Context:
- Significant rates of slow labor progress and augmentation occur in pregnant populations.
- Discrepancies exist between midwives and obstetricians regarding normal labor duration.
- Current definitions and durations of labor stages lack consistent scientific consensus.
Purpose:
- To review existing literature, including textbooks, guidelines, and studies, on the definitions and duration of the first and second stages of labor.
- To identify variations in the definition of labor onset, its phases, and duration across different sources.
- To assess the scientific basis for defining normal labor duration.
Summary:
- A review of eight textbooks, seven guidelines, and nine studies revealed significant variability in defining the onset and duration of labor stages.
- While the active phase of the first stage of labor was consistently defined by cervical dilatation (3-4 cm), other definitions varied widely.
- The end of the second stage was universally defined as the baby's birth, but its phases were inconsistently described.
Impact:
- The lack of a scientifically supported definition for normal labor duration contributes to the high assessment of slow labor progress.
- Systematic recording of labor duration is recommended to improve clinical assessment and patient care.
- Further prospective research is needed to establish evidence-based guidelines for labor duration, consequences of prolonged labor, and optimal intervention timing.
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