How many inductions lead to cesarean

Induction at 39 weeks versus waiting for labor When someone gets closer or past their due date, they will often face the question about whether to induce labor or wait for labor to start on its own.

Cautions about the evidence on inducing for due dates Before we begin discussing the evidence, it is important to note that there are some major drawbacks to the evidence that we have so far on induction versus waiting for labor to start: Many of the clinical trials were carried out in countries or time periods with low Cesarean rates.

For example, does your hospital put strict time limits on the length of labor, not allow people in labor to eat or drink at will, or discourage mobility and position changes during labor?

If so, then this evidence may not apply to you, because induction may be more risky more likely to lead to a Cesarean in your specific hospital! As we discussed, the appropriate comparison group for elective induction includes people who are induced later in the pregnancy together with those who go into labor spontaneously.

For example, in the Hannah Post-Term trial the biggest study about induction for post-dates , about one-third of mothers who were assigned to the induction group went into labor spontaneously before the induction. When you look at the breakdown of what actually happened to the people in the two groups as we do below , it becomes apparent that Cesarean rates are only increased with expectant management when induction occurs later in the pregnancy, and not when mothers go into spontaneous labor later in the pregnancy.

This extra testing may have led to higher rates of Cesarean section for suspected fetal distress during labor in the expectant management group Wood et al. The induction protocols varied from study to study, and even within studies themselves. For example, in the Hannah Post-Term study, people in the active management group first received drugs to ripen the cervix, and then drugs to induce labor. Meanwhile, people in the expectant management group who ended up being induced did NOT have cervical ripening.

It is known that medical induction without cervical ripening results in higher risk of Cesarean, so in this case, the expectant management group would have been at increased risk of Cesarean compared to the active management group.

The ARRIVE study of week inductions In , researchers published the results of the ARRIVE study A Randomized Trial of Induction Versus Expectant Management , conducted to find out if elective induction of labor during the 39th week of pregnancy would result in a lower rate of death and serious complications for babies, compared to waiting until at least 40 weeks and 5 days for elective induction Grobman et al. Some mothers may not benefit from early elective induction, including: Those who prefer to avoid medical interventions.

Many mothers would prefer to wait for labor to start on its own, if possible. Some mothers want to avoid cervical ripening drugs, synthetic oxytocin, or mechanical induction with a Foley catheter, where an inflatable balloon presses against the cervix to help start labor. They may also want to avoid other medical interventions that go along with induction, such as intravenous fluids, continuous fetal monitoring, and restrictions on freedom of movement.

Those whose care providers have high Cesarean rates with inductions. Those choosing midwifery care. Studies show that midwives achieve low rates of Cesarean without the regular use of elective induction. Retrospective studies of week induction in recent years We found five retrospective studies conducted in the last five years that compared week elective induction with expectant management.

Table 1. Retrospective studies of elective induction at 39 weeks versus expectant management. Induction at 39 weeks versus waiting for labor We considered the evidence discussed above in a broader context to develop the following list of potential Pros and Cons of week elective induction.

No maternal deaths occurred in either group. The researchers did not report on uterine rupture. For babies: Babies in the elective induction group had a lower composite adverse outcome rate 1.

One stillbirth occurred in the elective induction group at 40 weeks and 6 days before the mother was induced and two stillbirths occurred in the expectant management group while the mothers were waiting for labor.

One was to a first-time mother at 41 weeks and 3 days; her baby was small for gestational age. The other stillbirth was to an experienced mother at 41 weeks and 4 days; her placenta showed signs of infection. There were no newborn deaths in either group.

There was no protocol for fetal monitoring it varied by local guidelines , but fetal monitoring and assessment of amniotic fluid levels was typically performed between weeks. For babies: The study was stopped early after five stillbirths and one early newborn death occurred in the expectant management group, out of 1, participants 4.

Zero deaths had occurred in the elective induction group, out of 1, participants. All five stillbirths in the expectant management group occurred between 41 weeks, 2 days and 41 weeks, 6 days. Three of the stillbirths had no known explanation, one was with a baby that was small for gestational age, and the other was with a baby who had a heart defect. The one newborn death occurred four days after birth due to multiple organ failure in baby that was large for gestational age.

The author mentions that when complications are present at the end of pregnancy e. All of these perinatal deaths occurred with first-time mothers, which suggests that week induction may be especially beneficial for first-time mothers. They found that it only took inductions at 41 weeks to prevent one perinatal death. This is a much lower number than previously thought. If you recall, the INDEX trial did not find a significant difference in perinatal death between the induction group and the expectant management group 1 versus 2 deaths, respectively.

It could also be that there was better fetal monitoring of participants between 41 and 42 weeks in the INDEX trial, leading to fewer perinatal deaths. There was no difference in the composite perinatal outcome 2. However, there was a significant difference in perinatal death alone. More mothers in the elective induction group had inflammation of the inner lining of the uterus usually due to infection, called endometritis 1.

There were no cases of uterine rupture in either group. In the induction group: Labor was induced within four days of entering the study usually about 4 days after 41 weeks. A maximum of 3 doses of gel were given every 6 hours.

If this did not induce labor or if the gel was not used, participants were given IV oxytocin, had their waters broken, or both. They could not receive oxytocin until at least 12 hours after the last prostaglandin gel dose. In the monitored expectant management group: Participants were taught how to do kick counts every day and had nonstress tests 3 times per week. The amniotic fluid level was checked by ultrasound times per week.

What did researchers find in the Hannah Post-Term study? The findings on Cesarean rates differ depending on which set of numbers you compare. What happened in the original, randomly assigned groups?

But what happened to people who were actually induced or actually went into labor on their own? The same pattern holds true when you look at experienced mothers people who had given birth before : So what do these numbers mean? Policy of routine induction before 42 weeks is still controversial The authors of a systematic review from raise concerns that routine induction prior to post-term puts a large number of pregnant people at risk of harmful side effects from induction Rydahl et al.

Are there any benefits to going past your due date? Based on the available evidence, Dr. Is it safe for someone to wait for labor to begin on its own, if that is what they prefer? How long is it safe to wait? How should people and their care providers talk about the risk of stillbirth?

Access our Talking about Due Dates Handout. The Ontario Midwives Association has a really comprehensive, easy-to-understand set of guidelines. To download the free PDF, click here. To download the Society of Obstetricians and Gynaecologists of Canada guidelines Canada , click here. In , ACOG reaffirmed their recommendations on post-term pregnancy.

Although their guidelines are not freely available to the public, ACOG recommends that induction of labor should take place between 42 weeks 0 days and 42 weeks 6 days, and that induction at 41 weeks can also be considered.

They concluded that it is reasonable to offer elective induction to low-risk, first-time mothers at 39 weeks of pregnancy. They expressed concern that many women may not desire elective induction and proposed that costs might be better spent on less invasive but more effective approaches to reduce Cesarean rates, such as continuous labor support from a doula.

The bottom line Current research evidence has found that elective induction at 39 weeks does not make a difference in the rate of death or serious complications for babies. We have heard from people who are surprised at this finding, since for so long elective induction was thought to increase the Cesarean rate.

It would be interesting to see secondary analyses published on who actually was induced versus who actually had spontaneous labor for every study like we saw with the Hannah Post-Term trial. But from a decision-making perspective, it is most helpful to consider the results according to original group assignment active versus expectant management , since spontaneous labor is not a guarantee with expectant management.

Elective induction at 41 weeks and 0 to 2 days could help to reduce stillbirths and poor health outcomes for babies, especially among first-time mothers. Importantly, two large randomized, controlled trials published in both found benefits to elective induction at 41 weeks instead of continuing to wait for labor until 42 weeks. One of the studies found fewer perinatal deaths with week induction and the other found fewer poor health outcomes for babies e.

An earlier study called the Hannah Post-Term study found that waiting for labor after 41 weeks greatly increased the risk of Cesarean for people who ended up needing an induction for medical reasons, but not for people who went into labor on their own.

The Bishop score that helps to determine if you are a good candidate for induction is based on five factors: How dilated or open is your cervix? How effaced or thin is your cervix? How soft is your cervix? How far forward is your cervix?

These non-medical factors are very real when it comes to individual decision-making. For example, the experience of being induced potentially more painful contractions, tethered to wires for monitoring and IV fluids, confined to bed may not make much of a difference to someone planning a birth with an epidural, but it can make a huge difference to someone planning to use movement and other comfort measures during an unmedicated birth.

On the other hand, someone who has experienced miscarriages or stillbirth in the past may have a strong preference for elective induction in order to lower the absolute risk of stillbirth by any means necessary. All of these experiences and preferences are valid. References: Alfirevic, Z. American College of Nurse Midwives Accessed online December 1, Committee opinion no. Obstet Gynecol , American College of Obstetricians and Gynecologists , Reaffirmed Committee Opinion No.

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Am J Obstet Gynecol 3 : e Perneger, T. J Gen Intern Med 26 12 : Rosenstein, M. Risk of stillbirth and infant death stratified by gestational age. Sanchez-Ramos, L. Similarly, the rate of blood pressure disorders of pregnancy was significantly lower in women who were induced 9. The researchers estimate that one cesarean delivery could be avoided for every 28 low-risk, first-time mothers undergoing elective induction at 39 weeks. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases.

For more information about NIH and its programs, visit www. Grobman, WA et al. Labor induction versus expectant management for low-risk nulliparous women. Site Menu Home. Search Health Topics. Search the NIH Guide. News Releases. News Release Wednesday, August 8, Induced labor at 39 weeks may reduce likelihood of C-section, NIH study suggests Elective induction at 39 weeks also linked to lower risk of maternal high blood pressure disorders.

References Grobman, WA et al. Back to Top.