Defining Failed Induction of Labor

Abstract

BACKGROUND: While there are well-accepted standards for the diagnosis of arrested active-phase labor, the definition of a "failed" induction of labor remains less certain. One approach to diagnosing a failed induction is based on the duration of the latent phase. However, a standard for the minimum duration that the latent phase of a labor induction should continue, absent acute maternal or fetal indications for cesarean delivery, remains lacking. OBJECTIVE: The objective of this study was to determine the frequency of adverse maternal and perinatal outcomes as a function of the duration of the latent phase among nulliparous women undergoing labor induction. STUDY DESIGN: This study is based on data from an obstetric cohort of women delivering at 25 US hospitals from 2008 through 2011. Nulliparous women who had a term singleton gestation in the cephalic presentation were eligible for this analysis if they underwent a labor induction. Consistent with prior studies, the latent phase was determined to begin once cervical ripening had ended, oxytocin was initiated, and rupture of membranes had occurred, and was determined to end once 5-cm dilation was achieved. The frequencies of cesarean delivery, as well as of adverse maternal (eg, postpartum hemorrhage, chorioamnionitis) and perinatal (eg, a composite frequency of seizures, sepsis, bone or nerve injury, encephalopathy, or death) outcomes, were compared as a function of the duration of the latent phase (analyzed with time both as a continuous measure and categorized in 3-hour increments).RESULTS: A total of 10,677 women were available for analysis. In the vast majority (96.4%) of women, the active phase had been reached by 15 hours. The longer the duration of a woman's latent phase, the greater her chance of ultimately undergoing a cesarean delivery (P < .001, for time both as a continuous and categorical independent variable), although >40% of women whose latent phase lasted !18 hours still had a vaginal delivery. Several maternal morbidities, such as postpartum hemorrhage (P < .001) and chorioamnionitis (P < .001), increased in frequency as the length of latent phase increased. Conversely, the frequencies of most adverse perinatal outcomes were statistically stable over time. CONCLUSION: The large majority of women undergoing labor induction will have entered the active phase by 15 hours after oxytocin has started and rupture of membranes has occurred. Maternal adverse outcomes become statistically more frequent with greater time in the latent phase, although the absolute increase in frequency is relatively small. These data suggest that cesarean delivery should not be undertaken during the latent phase prior to at least 15 hours after oxytocin and rupture of membranes have occurred. The decision to continue labor beyond this point should be individualized, and may take into account factors such as other evidence of labor progress.

Association between early amniotomy in labour induction and severe maternal and neonatal morbidity

“…Given the retrospective cohort study design, we were limited to the data collected from the original study and, as such, we do not have outcomes such as the timing of specific cervical ripening methods or the aetiology for the three neonatal deaths in our cohort. Lastly, given the caesarean delivery rate (17% for nulliparous and 2% for multiparous women), and the time period of data collection (2002–2007 before the shift in contemporary definition of active labour from 4 to 6 cm), our results may not be generalisable to all populations.…”

Failure of labor induction in Tigray region, Ethiopia: a retrospective record review study

“…Refers to the iatrogenic stimulation of uterine contractions before the onset of spontaneous labor to accomplish vaginal delivery after 28 weeks of gestation [1,4].…”

“…Induction of labour should be used only when the bene ts to the fetus or mother of the baby outweigh those of the pregnancy continuing [1][2][3]. Induction of labour has become an increasingly utilized obstetric intervention [4,5]. Induction maybe advocated to reduce fetal or neonatal morbidity and mortality as with post-term pregnancy, oligohydramnios, suspected intrauterine growth restriction (IUGR) and fetal gastroschisis, to reduce maternal morbidity, as with maternal cardiac disease and preeclampsia/eclampsia, or to bene t both maternal and fetal as with pre-labour rupture of membranes (PROM) at term and fetal macro-somia.…”

Role of Assessing Cervical Length by Transvaginal Ultrasound before Induction of Labour

“…within 15 hours and that maternal adverse events become more frequent with greater time in the latent phase. [12] In this study, we considered women with a Bishop score of less than 5 for induction as these are the ideal patients for induction of labour. A previous study has reported very unfavourable Bishop score on admission as predictive of caesarean section.…”