This is a plain English summary of an original research article
For women having their first baby with an epidural and/or spinal anaesthetic for pain-relief, the timing of pushing after full dilatation of the cervix does not affect the numbers that achieve normal vaginal delivery.
The best management for the second stage of labour is still debated. In the UK epidurals are by far the most widely used regional anaesthetic technique for pain relief in labour.
In this large trial, women either pushed immediately or delayed pushing by waiting for 60 minutes. Women in the immediate group ended up pushing for slightly longer, but their labour was 30 minutes shorter overall. They also had a lower risk of bleeding and infection.
Although this was a USA-based study the findings may help to inform practice in the UK.
Why was this study needed?
Labour is divided into the first stage when regular contractions start, and the second and third stages. The second stage of labour begins at complete cervical dilatation and is also known as the pushing stage. It ends when the baby is born.
Some evidence suggests that in women who have epidural and/or spinal anaesthesia, delayed pushing may encourage spontaneous vaginal delivery and reduce the need for interventional delivery. Other evidence suggests that there is no difference in spontaneous vaginal delivery rates between immediate and delayed pushing.
Up to 1 in 5 women in England have an epidural for pain management during labour. Instrumental delivery and prolonged labour can both lead to adverse outcomes, and so it is important to have good research to address the issue. This large trial was designed to provide stronger evidence to resolve the practical question of when the ideal time to start pushing in these circumstances.
What did this study do?
This randomised controlled trial was conducted at six centres across the United States. It included 2,414 women having their first baby, who had gone into either spontaneous or induced labour and had received epidural (+/- spinal) anaesthesia. Once reaching full cervical dilation (10cm), they were randomised to begin pushing immediately or to delay for 60 minutes (unless they had an irresistible urge or were instructed otherwise). Other aspects of care were unchanged.
The target recruitment was 3,184, but the trial terminated early due to safety concerns in the delayed group in the face of no apparent benefit.
Around two-thirds of eligible women invited to the study declined participation. Management of labour and technique of pushing were not measured. Some aspects of practice, such as the rate of epidural, may not be applicable to the UK.
What did it find?
- Rates of spontaneous vaginal delivery were similar in the immediate pushing group (85.9%) and delayed pushing group (86.5%). Neither was there difference in the rates of assisted deliveries (forceps or ventouse) or caesarean.
- The second stage of labour was on average 31.8 minutes shorter (95% confidence interval [CI] -36.7 to -26.9 minutes) shorter in the immediate group at 102.4 minutes compared with 134.2 minutes in the delayed group. The duration of active pushing was 9.2 minutes longer in the immediate group (95% CI +5.8 to +12.6 minutes).
- Immediate pushing was associated with lower rates of postpartum haemorrhage at 2.3% compared with 4.0% in the delayed group (relative risk [RR] 0.6, 95% CI 0.3 to 0.9), and infection of fetal membranes (chorioamnionitis) at 6.7% compared with 9.1% (RR 0.70, 95% CI 0.66 to 0.90).
- There was no difference between groups in the rate of neonatal morbidity (7.3% immediate vs 8.9% delayed; RR 0.8, 95% CI 0.6 to 1.1). Neither was there difference in the overall rate of perineal tears, which were common and affected 46% of both groups. However, third-degree tears (extending to the anal muscle) were borderline more common in the immediate pushing group (5.3% vs 4.3% delayed group; RR 1.2, 95% CI 1.0 to 1.4).
- Patient satisfaction with the second stage of labour did not differ between groups, and both groups similarly reported feeling in control.
What does current guidance say on this issue?
The NICE guideline on care during labour (updated 2017) advises that in women who have an epidural (and combined spinal-epidural), pushing should be delayed for at least one hour after full cervical dilation and longer if the woman wishes. Women without an epidural should be guided by their own urge to push.
The Royal College of Obstetricians and Gynaecologists guideline on assisted (operative) delivery (2011) state that delayed pushing in women with an epidural can reduce the need for deliveries that require forceps to rotate the baby’s head or because the head is too high in the birth canal.
What are the implications?
This large study raises a question regarding current practice that recommends delayed pushing in women having their first baby and who are receiving epidural and or spinal anaesthesia. It wasn’t found to reduce risk of assisted delivery.
The study may be less reliable for detecting a difference in other outcomes, such as postpartum haemorrhage and chorioamnionitis. However, there is a possibility that prolonging the second stage of labour is associated with adverse maternal and neonatal outcomes.
It is worth noting that many women, when asked, declined to participate in this trial. It’s unclear how management factors, such as positioning, may affect outcomes which may also vary between the US and the UK.
This study suggests no benefit from delayed pushing, but further research is needed to improve our understanding of this issue in UK practice.
Citation and Funding
Cahill AG, Srinivas SK, Tita AT et al. Effect of immediate vs delayed pushing on rates of spontaneous vaginal delivery among nulliparous women receiving neuraxial analgesia: a randomized clinical trial. JAMA. 2018;320(14):1444-54.
This trial was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and by funding from the Department of Obstetrics and Gynaecology, School of Medicine, Washington University in St Louis.
NHS Digital. NHS maternity statistics, England 2017-2018. London: NHS Digital; 2018.
NHS Digital. NHS maternity statistics, England 2016-17. London: NHS Digital; 2017.
NICE. Intrapartum care for healthy women and babies. CG190. London: National Institute for Health and Care Excellence; 2014, updated 2017.
RCOG. Operative vaginal delivery. London: Royal College of Obstetricians and Gynaecologists; 2011.
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