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Multicenter Study
. 2010 Dec;116(6):1281-1287.
doi: 10.1097/AOG.0b013e3181fdef6e.

Contemporary patterns of spontaneous labor with normal neonatal outcomes

Jun Zhang  1 , Helain J Landy, D Ware Branch, Ronald Burkman, Shoshana Haberman, Kimberly D Gregory, Christos G Hatjis, Mildred M Ramirez, Jennifer L Bailit, Victor H Gonzalez-Quintero, Judith U Hibbard, Matthew K Hoffman, Michelle Kominiarek, Lee A Learman, Paul Van Veldhuisen, James Troendle, Uma M Reddy; Consortium on Safe Labor
Affiliations
Multicenter Study

Contemporary patterns of spontaneous labor with normal neonatal outcomes

Jun Zhang et al. Obstet Gynecol. 2010 Dec.

Abstract

Objective: To use contemporary labor data to examine the labor patterns in a large, modern obstetric population in the United States.

Methods: Data were from the Consortium on Safe Labor, a multicenter retrospective study that abstracted detailed labor and delivery information from electronic medical records in 19 hospitals across the United States. A total of 62,415 parturients were selected who had a singleton term gestation, spontaneous onset of labor, vertex presentation, vaginal delivery, and a normal perinatal outcome. A repeated-measures analysis was used to construct average labor curves by parity. An interval-censored regression was used to estimate duration of labor, stratified by cervical dilation at admission and centimeter by centimeter.

Results: Labor may take more than 6 hours to progress from 4 to 5 cm and more than 3 hours to progress from 5 to 6 cm of dilation. Nulliparous and multiparous women appeared to progress at a similar pace before 6 cm. However, after 6 cm, labor accelerated much faster in multiparous than in nulliparous women. The 95 percentiles of the second stage of labor in nulliparous women with and without epidural analgesia were 3.6 and 2.8 hours, respectively. A partogram for nulliparous women is proposed.

Conclusion: In a large, contemporary population, the rate of cervical dilation accelerated after 6 cm, and progress from 4 cm to 6 cm was far slower than previously described. Allowing labor to continue for a longer period before 6 cm of cervical dilation may reduce the rate of intrapartum and subsequent repeat cesarean deliveries in the United States.

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Figures

Figure 1
Figure 1
Diagram of patient selection.
Figure 2
Figure 2
Average labor curves by parity in singleton, term pregnancies with spontaneous onset of labor, vaginal delivery and normal neonatal outcomes. P0: nulliparas; P1: women of parity 1; P2+: women of parity 2 or higher.
Figure 3
Figure 3
The 95th percentiles of cumulative duration of labor from admission among singleton, term nulliparas with spontaneous onset of labor, vaginal delivery, and normal neonatal outcomes.
Figure 4
Figure 4
Labor progression in 3 patients (A, B, C). Each letter represents a pelvic examination for the corresponding patient. The stair lines are the 95th percentile of cumulative duration of labor from admission at 2, 3, 4, 5 cm of cervical dilation, respectively.
See this image and copyright information in PMC

Comment in

  • Zhang's guideline to assess labour progression.
    Grylka-Baeschlin S, Devane D. Grylka-Baeschlin S, et al. Lancet. 2019 Jan 26;393(10169):300-301. doi: 10.1016/S0140-6736(18)32274-8. Epub 2018 Dec 20. Lancet. 2019. PMID: 30581040 No abstract available.

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    1. Zhang J, Troendle J, Reddy U, Laughon SK, Branch DW, Burkman R, Landy HJ, Hibbard JU, Haberman S, Ramirez MM, Bailit JL, Hoffman MK, Gregory KD, Gonzalez-Quintero VH, Kominiarek M, Learman LA, Hatjis CG, Van Veldhuisen P. Contemporary cesarean delivery practice in the United States. Am J Obstet Gynecol (in press) - PMC - PubMed

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