Progression of the first stage of spontaneous labour: A prospective cohort study in two sub-Saharan African countries.

PLoS Med 2018 01 16;15(1):e1002492. Epub 2018 Jan 16.

UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), Department of Reproductive Health and Research, World Health Organization, Geneva, Switzerland.

Background: Escalation in the global rates of labour interventions, particularly cesarean section and oxytocin augmentation, has renewed interest in a better understanding of natural labour progression. Methodological advancements in statistical and computational techniques addressing the limitations of pioneer studies have led to novel findings and triggered a re-evaluation of current labour practices. As part of the World Health Organization's Better Outcomes in Labour Difficulty (BOLD) project, which aimed to develop a new labour monitoring-to-action tool, we examined the patterns of labour progression as depicted by cervical dilatation over time in a cohort of women in Nigeria and Uganda who gave birth vaginally following a spontaneous labour onset.

Methods And Findings: This was a prospective, multicentre, cohort study of 5,606 women with singleton, vertex, term gestation who presented at ≤ 6 cm of cervical dilatation following a spontaneous labour onset that resulted in a vaginal birth with no adverse birth outcomes in 13 hospitals across Nigeria and Uganda. We independently applied survival analysis and multistate Markov models to estimate the duration of labour centimetre by centimetre until 10 cm and the cumulative duration of labour from the cervical dilatation at admission through 10 cm. Multistate Markov and nonlinear mixed models were separately used to construct average labour curves. All analyses were conducted according to three parity groups: parity = 0 (n = 2,166), parity = 1 (n = 1,488), and parity = 2+ (n = 1,952). We performed sensitivity analyses to assess the impact of oxytocin augmentation on labour progression by re-examining the progression patterns after excluding women with augmented labours. Labour was augmented with oxytocin in 40% of nulliparous and 28% of multiparous women. The median time to advance by 1 cm exceeded 1 hour until 5 cm was reached in both nulliparous and multiparous women. Based on a 95th percentile threshold, nulliparous women may take up to 7 hours to progress from 4 to 5 cm and over 3 hours to progress from 5 to 6 cm. Median cumulative duration of labour indicates that nulliparous women admitted at 4 cm, 5 cm, and 6 cm reached 10 cm within an expected time frame if the dilatation rate was ≥ 1 cm/hour, but their corresponding 95th percentiles show that labour could last up to 14, 11, and 9 hours, respectively. Substantial differences exist between actual plots of labour progression of individual women and the 'average labour curves' derived from study population-level data. Exclusion of women with augmented labours from the study population resulted in slightly faster labour progression patterns.

Conclusions: Cervical dilatation during labour in the slowest-yet-normal women can progress more slowly than the widely accepted benchmark of 1 cm/hour, irrespective of parity. Interventions to expedite labour to conform to a cervical dilatation threshold of 1 cm/hour may be inappropriate, especially when applied before 5 cm in nulliparous and multiparous women. Averaged labour curves may not truly reflect the variability associated with labour progression, and their use for decision-making in labour management should be de-emphasized.

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pmed.1002492DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5770022PMC
January 2018
76 Reads

Publication Analysis

Top Keywords

labour
24
labour progression
24
cervical dilatation
20
spontaneous labour
12
duration labour
12
multiparous women
12
women
11
women augmented
8
labour curves
8
oxytocin augmentation
8
multistate markov
8
progression
8
cumulative duration
8
nulliparous women
8
augmented labours
8
nigeria uganda
8
nulliparous multiparous
8
hours progress
8
cohort study
8
dilatation
6

References

(Supplied by CrossRef)
The graphic analysis of labor
E Friedman et al.
Am J Obstet Gynecol 1954
Primigravid labor; a graphicostatistical analysis
EA Friedman et al.
Obstet Gynecol 1955
Labor in multiparas; a graphicostatistical analysis
EA Friedman et al.
Obstet Gynecol 1956
Computer analysis of labour progression
EA Friedman et al.
J Obstet Gynaecol Br Commonw 1969
Computer analysis of labor progression. II. Distribution of data and limits of normal
EA Friedman et al.
T J Reprod Med 1971
Computer analysis of labor progression. 3. Pattern variations by parity
EA Friedman et al.
J Reprod Med 1971
Computer analysis of labor progression. IV. Diagnosis of secondary arrest of dilatation
EA Friedman et al.
J Reprod Med 1971
Evolution of graphic analysis of labor
EA Friedman et al.
Am J Obstet Gynecol 1978
The labor curve
EA Friedman et al.
Clin Perinatol 1981
Active management of labor
K O'Driscoll et al.
BMJ 1973

Similar Publications