The timing of second stage pushing efforts does not impact the rate of spontaneous vaginal delivery among nulliparous women receiving neuraxial anesthesia, according to a new study published in the Journal of the American Medical Association.
Alison G. Cahill, Department of Obstetrics and Gynecology, School of Medicine, Washington University in St Louis, St Louis, Missouri, and colleagues conducted the study to evaluate whether immediate or delayed pushing results in higher rates of spontaneous vaginal delivery and lower rates of maternal and neonatal morbidities.
For the study, the research team conducted a randomized clinical trial of nulliparous women at or beyond 37 weeks of gestation admitted for spontaneous or induced labor with neuraxial analgesia. Recruitment was terminated with 2414 of 3184 planned participants due to suggested futility for the primary outcome (spontaneous vaginal delivery) in the interim analysis. Participants who reached complete cervical dilation were instructed to begin pushing immediately or wait 60 minutes (1200 and 1204 women, respectively, completed the trial).
The primary outcome was spontaneous vaginal delivery. Secondary outcomes included a total duration of the second stage, duration of active pushing, operative vaginal delivery, cesarean delivery, postpartum hemorrhage, chorioamnionitis, endometritis, perineal lacerations (≥second degree), and a composite outcome of neonatal morbidity that included neonatal death and 9 other adverse outcomes.
- The rate of spontaneous vaginal delivery was 85.9% in the immediate group vs 86.5% in the delayed group, and was not significantly different (absolute difference, −0.6% [95% CI, −3.4% to 2.1%]; relative risk, 0.99 [95% CI, 0.96 to 1.03]).
- There was no significant difference in 5 of the 9 prespecified secondary outcomes reported, including the composite outcome of neonatal morbidity (7.3% for the immediate group vs 8.9% for the delayed group; between-group difference, −1.6% [95% CI, −3.8% to 0.5%]) and perineal lacerations (45.9% vs 46.4%, respectively; between-group difference, −0.4% [95% CI, −4.4% to 3.6%]).
- The immediate group had significantly shorter mean duration of the second stage compared with the delayed group (102.4 vs 134.2 minutes, respectively; mean difference, −31.8 minutes [95% CI, −36.7 to −26.9], P < .001), despite a significantly longer mean duration of active pushing (83.7 vs 74.5 minutes; mean difference, 9.2 minutes [95% CI, 5.8 to 12.6], P < .001), lower rates of chorioamnionitis (6.7% vs 9.1%; between-group difference, −2.5% [95% CI, −4.6% to −0.3%], P = .005), and fewer postpartum hemorrhages (2.3% vs 4.0%; between-group difference, −1.7% [95% CI, −3.1% to −0.4%], P = .03).
“These findings may help inform decisions about the preferred timing of second stage pushing efforts when considered with other maternal and neonatal outcomes,” concluded the authors.
For further reference log on to 10.1001/jama.2018.13986