Healthy Birth Practice #1 & The ARRIVE Trial

The foundation for the knowledge and skills taught in today's Lamaze childbirth classes are based upon healthy birth practices adapted from the World Health Organization (WHO). The first healthy birth practice taught in a Lamaze series is to let labor begin on its own. This isn't just because we're old school of course! This is because in the last weeks of a pregnancy, both mom and baby are getting ready for birth. During this precious time, there are many different processes that are happening and systems that are moving forward to have everything culminate and coordinate in the labor and birth. Each and every one of these processes are critical to a healthy baby and a mother's body that is ready for labor. In fact, one of the last organs to fully develop and mature in utero for baby are the lungs. When baby's lungs are fully ready for breathing in the outside world, they secrete a protein in utero that initiates labor at term. Before reading any further, please be aware that this article is about ELECTIVE (non-medically indicated) induction ONLY--this post does NOT apply to medically indicated induction.

If you're here, you probably have already heard of the ARRIVE trial, but perhaps this is your first time hearing about it. In 2018, there was a study completed that compared outcomes for induction in nulliparous women at 39 weeks gestation versus expectant management. Since the completion of this study, many providers have been citing the study to offer expectant mothers elective induction at 39 weeks. You can read the full article here. However, what many birth workers would love for mamas to know is that this study may not even apply to them for various reasons. As a childbirth educator and occasional birth doula, I fully support a woman's right to make decisions about her birth and her baby. I highly value education and acknowledge that it is a pre-requisite to INFORMED choice (because really, is an UN-informed choice really a choice?!), which is why I'm here to break down the ARRIVE trial in an impartial manner, help you see why this study would or wouldn't apply to you, and finally to help you determine whether an elective induction at 39 weeks aligns with your values and preferences.

Initially, the study screened over 50,000 women, but only less than half of them were deemed eligible for the study. Of the remaining eligible, only 27% agreed to participate in the study. At the end of the day, the study consisted of 6106 women and was randomized; but, this study was not blind. Parents and providers could not be blinded to which group they were allocated.

Women assigned to the induction group were induced anywhere between 39 weeks and 0 days to 39 weeks and 4 days. Women in the expectant management group were given until 40 weeks 5 days to go into labor spontaneously before also typically being induced. Yes, you read that correctly, the expectant management group also included inductions.

In this study, women in the induction group were found less likely to have a cesarean birth in comparison to those in the expectant management group (19% versus 22%), which isn't a huge difference and surprisingly still below the national average cesarean rate of 31%. Women in the induction group were also less likely to experience preeclampsia and/or gestational hypertension in comparison to the expectant management group (9% versus 14%). This, I feel, is a good place to add that continuous labor support, especially from doulas, have been proven to lower the cesarean rate, so if risk of a cesarean birth is your ONLY reason for an elective induction, take a look at Rebecca Decker's article on the evidence of doulas here where she cites a study by Bohren et.al in 2017 that concluded women who had continuous labor support experienced a 25% decrease in risk of cesarean birth, and even higher when that support was from a doula, with a 39% decrease.

What's important to note is that this study showed no statistically significant differences in adverse perinatal outcomes between the two groups.

I also think that it is imperative that we also consider the unique and strict induction protocols that were followed in this trial as they aren't representative of all inductions. First of all, all inductions used a cervical ripener first. Secondly, women were given twelve full hours of early labor before they were labeled as 'failure to progress' (one of the leading reasons inductions become cesareans in the first place). It is important to bear in mind that many induction protocols aren't as generous as 12 hours.

As a result of the ARRIVE trial, obstetrics practices across the U.S. have adapted their clinical practice in light of this new data. Laura Gilroy, MD, set out to conduct a study to determine the implications of these changes on perinatal outcomes after the ARRIVE trial publication. This study was done by comparing low-risk nulliparous women with singleton babies who delivered at or after 39 weeks between between January 1, 2015 and December 31, 2017 (the pre-ARRIVE group) to women who delivered between January 1, 2019 and December 31, 2019 (post-ARRIVE group). Results from the study showed a "small but statistically significant increase in some adverse maternal and neonatal outcomes" (Gilroy, 2022, para 5). The increase in adverse neonatal outcomes included an increased trend toward needing assisted ventilation at birth and being more likely to have low 5-minute APGAR scores than the pre-ARRIVE group. There were no differences in admissions to the NICU and/or neonatal seizures between the two groups. While the post-ARRIVE group had a smaller rate of cesarean birth, they were more likely to receive a blood transfusion and/or be admitted into the ICU. While this study is just a comparison of obstetrical trends before and after the ARRIVE trials and do not necessarily indicate causation, it is worth exploring further to see if the changes in obstetric practices are causing this increase in adverse maternal and neonatal outcomes. You can see the full study here.

So, here we are now. You've read this blog and the articles cited, perhaps did a little research on your own, and you still find that an elective induction at 39 weeks DOES align with your values and preferences, it is important to determine whether your care provider adheres to protocols that will maximize your chances of a healthy vaginal birth by asking them the following questions:

• Will I be given a cervical ripener prior to the induction?

• Once Pitocin is started, as long as baby and I are fine, how long do I have to go into active labor?

• What do you consider active labor? (ACOG recommends 6 cm--see study here).

• What criteria is used to determine I'm not progressing in a satisfactory manner to birth vaginally once in active labor?

The same ACOG article cited above defines active phase arrest as "at or beyond 6 cm dilation with ruptured membranes who fail to progress despite 4 hours of adequate uterine activity, or at least 6 hours of oxytocin administration with inadequate uterine activity and no cervical change" (ACOG, 2016, Table 3).

• Once active labor is established, will you stop Pitocin?

A study by Saccone (2017) here concluded that the discontinuation of Pitocin once active labor was established reduced risk of cesarean from 14.7% to 9.3%).

• How long will I be given during the pushing phase before being considered for an arrest of labor?

The ACOG article cited above advises at least 2 hours of pushing in multiparous women and at least 3 hours of pushing in nulliparous women before a diagnosis of labor arrest is made (ACOG, 2016, Table 3).