Maternal and Neonatal Consequences of Early Augmentation of Labor Among Women With Spontaneous Onset of Labor: A National Population-Based Study.

Background: While some labor interventions are essential in preventing maternal and neonatal morbidity, there is little evidence to support systematic early augmentation of labor (EAL). Our objective was to assess the association between EAL and cesarean delivery rate, postpartum hemorrhage and adverse neonatal outcomes.

Methods: Population-based study using data from the 2016 French Perinatal Survey. Women with a singleton cephalic fetus, delivering at term after a spontaneous labor were included. "EAL" was defined by artificial rupture of the membranes (AROM) and/or oxytocin within 1 h of admission and/or duration between interventions of less than 1 h. Women without EAL were women without labor augmentation or without EAL. The primary endpoint, cesarean delivery and the secondary endpoints were compared between women with and without EAL using univariate analysis. A multivariable logistic regression was adjusted on the suspected confounders and a propensity score approach was then performed.

Results: Among the 7196 women included, 1524 (21.2%) had EAL. Cesarean delivery rates were significantly higher in the EAL group compared with the no EAL group, 8.40% versus 6.15% (p < 0.01). EAL was associated with cesarean delivery in the multivariable analysis aOR 1.45 95% CI [1.15-1.82] and in the cohort matched on the propensity score, OR 1.56 [1.17-2.07]. EAL was not associated with severe postpartum hemorrhage, low 5-min Apgar score, low neonatal cord pH or transfer to NICU.

Conclusion: EAL is frequent, involving one in five spontaneous laboring women in France. This practice is associated with an increased cesarean delivery risk.