The expected labor progression after labor augmentation with oxytocin: A retrospective cohort study

Abstract

ObjectiveTo describe labor progression patterns with oxytocin for augmentation in women who achieve vaginal delivery; and to determine how long one should wait with effective uterine contraction before labor arrest can be diagnosed.DesignPopulation-based retrospective cohort study.PopulationThe final sample involved 8,988 women with singleton gestation, term live birth, vertex presentation, no previous cesarean section, vaginal delivery, and neonatal Apgar score at 5 minutes at 7 or higher, and complete information on oxytocin augmentation in 2005–2007.MethodsLinear interpolation was used from the vaginal exam records for each woman to estimate the cervical dilation when oxytocin was started and the highest dose was first reached by parity. We used survival methods to estimate quartiles of the traverse time distributions of cervical dilation.Main outcome measuresDuration of labor under oxytocin augmentation.ResultsWhen oxytocin was just started, it took a long time to observe cervical dilation. The 50th(95th) centiles of the time interval from 4 to 5 cm, 5 to 6 cm, and 6 to 10 cm dilation were 2.9(8.8) hr, 1.7(5.8) hr, and 2.1(6.0) hr in nulliparas; and 3.1(10.1) hr, 1.9(8.0) hr, and 1.7(6.2) hr in multiparas. After effective uterine contractions were achieved under oxytocin, labor progressed much faster. The corresponding values were 0.7(2.4)hr, 0.5(1.5)hr, and 0.5(1.5)hr in nulliparas; and 0.6(1.9)hr, 0.4(1.1)hr, and 0.4(0.9)hr in multiparas. Low- and high-dose oxytocin regimens had similar effects on labor.ConclusionWhen oxytocin is just started for labor augmentation in early first stage, it may take up to 10 hours for the cervix to dilate by 1 cm. Once effective uterine contractions are achieved and the cervix is dilated more than 5 cm, cervical dilation to the next centimeter occurs within 2 hrs in both nulliparas and multiparas in 95% of the cases. High- and low-dose oxytocin had a similar impact on labor progression in augmented labor.

Oxytocin administration for induction and augmentation of labour in Polish maternity units– an observational study

“…Several studies have compared the results of high and low-dose oxytocin administration regimens [15,23]. Still, few have focused on the duration of the oxytocin infusion and total amount administrated, dose-escalation and intervals and outcomes for women and babies [24][25][26][27]. Studying these aspects is particularly crucial in the light of the latest reports on the longer than the previously believed half-life of oxytocin that can lead to high accumulation and unnecessary exposure in women and children [28].…”

Risk factors of uterine contraction after ureteroscopy in pregnant women with renal colic

“…The results also reminded us that routine monitoring of uterine contractions after ureteroscopy might help to avoid pregnancy complications. Compared with primipara, the cervix of multipara is easier to expand, which means a sooner labor process [21,22]. Literature has shown that uterine contraction was stronger for multipara during labor and more analgesics were needed for painless delivery [23].…”

Risk Factors of Uterine Contraction After Ureteroscopy in Pregnant Women With Renal Colic

“…Compared with primipara, the cervix of multipara is easier to expand, which means a sooner labor process [21,22] . Uterine contraction is stronger for multipara during labor and more analgesics are needed for painless delivery [23] .…”