Recommendations in the US have changed when it comes to the safety of ‘laboring down’ with an epidural but the new recommendations just don’t add up. I assumed everybody else in the birth world thought that ACOG had made a mistake especially as it’s supported by other obstetric organizations. That was until I had questions about my article on epidural birth preferences on social media recently.

Put on the kettle and settle in for a long and (hopefully interesting) read - with a few plot twists!

What is Laboring Down?

Laboring down (also known as passive descent). The practice of “laboring down” or delayed pushing is common in hospital births with an epidural. Once a woman's cervix is fully dilated to 10 centimeters, she rests for one to two hours before she starts actively pushing with the surges/contractions.

If you’re just beginning to learn about what happens in labor and birth you might be wondering why on earth would you NOT push once you’re fully dilated? Many first time moms don’t know that your body will keep on nudging your baby towards the exit even if you’re sleeping. With a dense epidural it’s very possible that you won’t be aware of how much progress your body is making without any effort from you until baby is very close to being born. You may not know that coached pushing (sustained breath holding) comes with tradeoffs for you and your baby including increasing your chances of tearing as well as impacting your cardiac output and other potential complications for you and your baby.

For most informed nurses and midwives, waiting for baby to move lower into the pelvis while mom rests is a no brainer. It reduces exhaustion for mom so she can conserve energy for the moment she meets her baby, starts to nurse and begins her postpartum recovery. It seems counterintuitive to exhaust moms even more unnecessarily.

2017 - ACOG Gets Focused on Evidence

ACOG published a paper in 2017 in favor of delaying pushing and and in support of avoiding unnecessary interventions in labor especially for first time moms. It seemed like they were starting to get it! Neel Shah was on the circuit presenting at birth conferences. The future was looking bright.

ACOG concluded:

“Nulliparous women who have an epidural and no indication for expeditious delivery may be offered a period of rest for 1-2 hours before initiating pushing efforts.”

During the same year the Cochrane Review shared its review of the evidence available at the time.

Timing of pushing with epidural is consistent in that delayed pushing leads to a shortening of the actual time pushing and increase of spontaneous vaginal delivery at the expense of an overall longer duration of the second stage of labour and an increased risk of a low umbilical cord pH (based only on one study).

2019 - ACOG - A Sudden Change of Advice

Considering how long it takes for evidence based practices to become routine (about 17 yrs) there were a LOT of eyebrows raised when ACOG flip flopped on their recommendation for first time moms with an epidural to labor down. On the basis of 1 study (not a meta-analysis) they changed their tune significantly. Childbirth organizations around the US shared this new recommendation with their childbirth educators and doulas without first exploring the findings.

“Collectively, and particularly in light of recent high- quality study findings, data support pushing at the start of the second stage of labor for nulliparous women receiving neuraxial analgesia. Delayed pushing has not been shown to significantly improve the likelihood of vaginal birth and risks of delayed pushing, including infection, hemorrhage, and neonatal acidemia should be shared with nulliparous women receiving neuraxial analgesia who consider such an approach.”

Just like the Breech Term Trial changed breech birth overnight - news of this trial travelled quickly and was adopted without question by many. Maybe we should take a look at what ACOG considers a ‘high quality study’ and how ACOG came to such a different recommendation in 1 year (not 17).

2018 - Cahill et al Say No To Delayed Pushing

Cahill and a group of about 15 Obstetricians published their study - Effect of Immediate vs Delayed Pushing on Rates of Spontaneous Vaginal Delivery Among Nulliparous Women Receiving Neuraxial Analgesia - A Randomized Clinical Trial.

When you look at a research paper one of the first parts is the ‘research question’. What was the actual issue the investigators were trying to solve?

Objective To evaluate whether immediate or delayed pushing results in higher rates of spontaneous vaginal delivery and lower rates of maternal and neonatal morbidities.

Of the 2414 first time moms recruited:

• Nearly half were induced.

• 80% were given Pitocin.

• Almost all of the births were managed by Doctors.

• 80% of women were coached to push.

What Did They Find?

They found that whether you did delayed or immediate pushing did not increase a mom’s risk of having a cesarean - there wasn’t really a difference. But there were differences in complications for moms and babies (but it’s far from black and white).

(DP = delayed pushing, IP = Immediate pushing).

• The rate of vaginal delivery was 85.9% in the IP (immediate pushing group) vs 86.5% in the DP (delayed pushing) and was not significantly different.

• The IP group had a significantly shorter 2nd stage compared with DP - around a 30-40 minute difference.

• Immediate pushing women experienced lower rates of chorioamnionitis (6.7% vs 9.1%).

• The authors claimed DP moms women had more postpartum hemorrhages (4.0% vs 2.3%) but their own data disagrees.

• The risk of 3rd and 4th degree injuries was significantly higher in the immediate pushing group compared with the delayed pushing group.

• Interestingly the shoulder dystocia rates in the DP group were 27 compared to 40 in the IP group (however it didn’t reach statistical significance).

What about the Babies?

Good news - A small similar number of babies went to NICU from both groups.

Bad news - There was more Chorioamnionitis (intra-amniotic infection). This infection occurs when bacteria enter any of the tissues or membranes around your baby.

If you Google ‘laboring down’ you’ll even come across an NPR piece giving the following advice based on this one trial:

Dr. Christopher Zahn, vice president of practice activities at the American College of Obstetricians and Gynecologists, says the take-home message is crystal clear: There are no significant benefits to delayed pushing, and delaying actually increases the risk of adverse events, particularly for the mother.

 Things That Make You Go Hmmmmmm

If you’re a birth professional some of the outcomes reported might have you scratching your head so I’ll share some of my thoughts - I’d love to hear yours. If you’re an expectant parent hold on to your hat!

1 - Here’s where it gets more interesting - the study was run in several hospitals in the US - hospitals that have c/s rates in the mid to high 20s (sadly nothing unusual there). So if women are receiving ‘usual care’ by staff in a study we’d expect to see the c/s rates to be similar during the trial but instead the authors report a c/s rate of about 8%. Yes - it looks like these authors are going to give The Farm a run for it’s money… It’s doubtful that these women received 'usual care’ - which makes this study less credible.

2 - PPH - Postpartum hemorrhage is the leading cause of maternal mortality.  It’s estimated that PPH is responsible for about 27% of maternal deaths. In the US - PPH causes approximately 11% of maternal deaths in the United States and is the leading cause of death.  Optimal management requires accurate blood loss recording.  This is important, as the number recorded may impact your decisions for future births. So why didn’t the authors use an evidence based accurate approach - namely ‘QBL’ - (quantitative blood loss). I don’t think it’s unreasonable for parents to ask for QBL in their medical documentation. In this study providers guessed the women’s blood loss - known as EBL (estimated blood loss) yes they guessed. International recommendations advise against guessing EBL and advise a more accurate approach (weighing soiled swabs, sponges, chucks etc). Guessing EBL can be inaccurate and commonly results in underestimation of high volumes and overestimation of low volumes especially if amniotic fluid is also present. Keep in mind blood loss from an epis or a tear may also increase the blood loss but it’s not a ‘true’ PPH. Guessing blood loss is notoriously inaccurate as seen in this 2022 study linked below.

 In a recent study on vaginal births providers most providers significantly overestimated blood loss volumes by nearly 700 mL.

 Plot Twist!

 In the same year ACOG flip/flopped about their recommendations for delaying pushing as an option passive descent they published a paper (#794) to improve accurate blood loss recording and concluded that “visual estimation is subjective and imprecise.”

ACOG seems to be talking out of both sides of their mouth.

In the most recent meta-analysis on delayed Vs immediate pushing no increase in PPH was reported (all of the included studies were considered ‘low quality’).

 3 - Tearing - is it at all surprising that women in the delayed pushing group experienced more serious perineal injury? What happens when a handsy provider is waiting for their catch (perineal stretching…even Baby Shampoo).

4 - One of the risks of chorioamnionitis are long labors especially when the waters are released. With around half of these moms being induced and having repeated vaginal exams there seems to be more to this especially as other trials didn’t have similar findings. It’s quite unlikely that this infection suddenly became an issue because mom didn’t push right away. In the 2020 meta-analysis the primary investigator reported that only Cahill & Tuuli’s study showed an increase in chorio.

Other Musings:
The station of baby was not recorded when pushing started. Most birth professionals know that a baby at -1 or 0 station in the pelvis needs more time to come down. Take a look at my Epidural Birth Preferences - a must read for birth professionals and parents.

The Obstetricians that were part of the Cahill study also seemed to think that moms without an epidural always start spontaneously pushing at 10cm (who wants to tell them) and since when do obstetricians stay for pushing? What position did the women give birth in? These ‘experts’ may never have even witnessed a 2-hr pushing stage as they usually only show up when baby’s head is visible. Severe perineal injury can be a life changing complication for some women but as it wasn’t a primary outcome being investigated it didn’t seem worthy of discussion.

Why is this an issue in the US when many other countries have no issues with safe laboring down?

With all of this to consider - is this research really trustworthy? Should ACOG reconsider their stance?

I hope this was helpful - as always talk to your colleagues, your healthcare provider and don’t be afraid to ask questions about new studies.

PS - if you’re one of those brilliant nurses/midwives who keep finding those pesky cervical lip problems so mom can labor down a bit longer (especially if it’s a pushy provider). Thank you!

If I missed something important please let me know!

Tracy