Differences in Inflammation, Intervention Rates, and Birth Outcomes in 'Active' and 'Pre-active' Labor Admission Groups
Loading...
Date
2011-06
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
The Ohio State University
Abstract
Laboring women are often admitted to labor units under criteria commonly associated with active labor onset, i.e., 3-5 cm dilatation + regular uterine contractions. However, active labor is only retrospectively determinable for any individual, thus, these criteria may not reliably describe true active labor onset. Evidence increasingly suggests that acute, feed-forward inflammatory processes are essential for optimal active labor progression. ‘Pre-active’ labor admissions followed by interventions to accelerate labor may interrupt important inflammatory processes, thereby predisposing women to unnecessary intrapartum interventions and more adverse labor outcomes. The purpose of this study was to compare ‘pre-active’ (i.e., <0.5 cm/hr for the first 4 hours post-admission) and active (i.e., ≥0.5 cm/hr for the first 4 hours post-admission) labor admission groups on the following parameters: inflammatory biomarkers (i.e., WBCs and maternal temperature); intervention rates (e.g., oxytocin augmentation); and labor outcomes (e.g., in-hospital labor duration). This study is a secondary analysis of a prior prospective study involving a convenience sample of low-risk, term, nulliparous women admitted for spontaneous labor onset between 3-5 cm dilatation (n=93). Of the subjects, 49.5% (n=46) were admitted in ‘pre-active’ labor. Inflammatory biomarkers did not differ between the ‘pre-active’ and active labor groups. The ‘pre-active’ group had higher rates of oxytocin augmentation (80.0% and 47.8%, respectively; x2=10.075; p<0.01), more cervical examinations (7.91 and 5.72, respectively; t=4.828; p<0.001), and longer in-hospital labor durations (10.95 and 6.97 hrs, respectively; t=5.858; p<0.001). These results imply that criteria commonly used to identify active labor onset are not reliable. ‘Pre-active’ labor admissions predispose women to more labor interventions and longer in-hospital durations. A more thorough assessment of labor status prior to admission is indicated to maximize the number of women admitted in active labor. This may allow physiological changes important to successful labor to more fully manifest, thereby decreasing unnecessary interventions and improving birth outcomes.
Description
Keywords
labor, labor admission, labor interventions, birth outcomes, active phase, nulliparas labor