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. Author manuscript; available in PMC: 2022 Apr 22.

American College of Nurse-Midwives Clinical Bulletin Number 18: Induction of Labor

American College of Nurse-Midwives1,Nicole Smith Carlson2,Alexis Dunn Amore2,Jessica Ann Ellis3,Katie Page4,Robyn Schafer5
1American College of Nurse-Midwives, Silver Spring, Maryland
2Emory University, Atlanta, Georgia
3University of Utah; President, UT Affiliate of ACNM
4President, RMWC Alumnae and Randolph College Alumni Association; President, VA Affiliate of ACNM
5Rutgers University, Newark, New Jersey
✉

Correspondence: Nicole Smith Carlson,Nicole.carlson@emory.edu

PMCID: PMC9026716  NIHMSID: NIHMS1796557  PMID:35119782
The publisher's version of this article is available atJ Midwifery Womens Health

Abstract

Induction of labor is an increasingly common component of intrapartum care in the United States. This rise is fueled by a nationwide escalation in both medically indicated and elective inductions at or beyond term, supported by recent research showing some benefits of induction over expectant management. However, induction of labor medicalizes the birth experience and may lead to a complex cascade of interventions. The purpose of this Clinical Bulletin is twofold: (1) to guide clinicians on the use of person-centered decision-making when discussing induction of labor and (2) to review evidence-based practice recommendations for intrapartum midwifery care during labor induction.

Keywords: induction of labor, indicated induction, elective induction, shared decision-making, intrapartum

INTRODUCTION

Induction of labor is the process of initiating labor through pharmacological or mechanical means.1 Currently, more than 25% of pregnant persons in the United States experience an induction of labor.2 Induction of labor is expected to become even more common in the future because of the increasing prevalence of persons who have complications during pregnancy, such as obesity and hypertension.3,4 In addition, elective induction of labor at term is becoming increasingly popular because of recent studies demonstrating its safety and efficacy with regard to the prevention of primary cesarean birth in certain low-risk populations.5,6

Midwives are guided by a philosophy which affirms the importance of nonintervention in normal processes, a person’s rights to self-determination and active participation in health care decisions, and the incorporation of scientific evidence into clinical practice.7 Certified nurse-midwives and certified midwives thus have an obligation to protect the normal physiologic processes of labor whenever possible, and to use labor interventions judiciously and optimally when needed or requested. The purpose of this Clinical Bulletin is twofold: (1) to guide clinicians on the use of person-centered decision-making around the induction of labor and (2) to review evidence-based practice recommendations for intrapartum midwifery care during induction of labor.

BACKGROUND

Starting in the early 1980s, the use of labor induction increased across the United States, involving 23.8% of births in 2010.8 Extensive use of labor induction during this time resulted in a nationwide shift toward younger gestational age at the time of birth. In response to concerns about the health of neonates born before 39 weeks’ gestation, there were widespread efforts to curtail the induction of labor at early-term gestations,9–11 which in 2011 successfully decreased induction rates for all births and most significantly for persons who were 38 weeks’ gestation or less.12 In contrast, induction of labor in pregnancies complicated by selected maternal or fetal risk factors at various gestational ages remains an important tool to improve outcomes.13,14 Depending on the presence of specific antepartum conditions, induction of labor might be optimally performed before term gestation in some cases, or near 42 0/7 weeks’ gestation in the case of persons seeking induction to avoid postterm pregnancy.15

In research on induction of labor performed before 2009, increased rates of cesarean birth were observed among pregnant persons who were electively induced compared with rates of those who experienced spontaneous labor, especially among nulliparous persons.16 However, in later research, investigators17 used a comparison group of persons who were expectantly managed (eg, either experienced spontaneous labor or labor induction over a variable period of watchful waiting) and found that elective induction of labor at term was not associated with increased cesarean birth18 or was associated with decreased rates of cesarean birth19 Corroborating these findings, healthy nulliparous persons randomized to term elective induction of labor at 39 weeks in the A Randomized Trial of Induction Versus Expectant Management (ARRIVE) study experienced cesarean birth at lower rates than with expectant management, despite the fact that nulliparous persons often begin induction of labor with lower Bishop scores than those of multiparous persons.5 The ARRIVE investigators estimated that 28 low-risk nulliparous persons would need to undergo elective induction of labor at 39 weeks’ gestation to prevent one cesarean birth. By contrast, there is recent observational evidence that in a midwifery model of care, cesarean birth rates may not differ in nulliparous persons who undergo labor induction compared to expectant management until later in gestation.20 In that study, authors found that within two midwifery practices (N = 4057 patients) with low overall use of cesarean birth and labor induction, there was no difference in the use of cesarean birth between the expectant management and labor induction groups until the 40th week. Only at that point in pregnancy did they see a decrease in midwifery clients’ odds of cesarean birth with labor induction compared to birth at 41 0/7 weeks or later following expectant management (odds ratio 0.57; [95% CI 0.36–0.90]).20 Although this observational study is of lower quality evidence than a prospective trial, it has the advantage of focusing on the unique context of the midwifery model of care.

There is also high-quality evidence that elective induction of labor for low-risk persons at 39 weeks’ gestation is protective against the development of hypertensive disorders of pregnancy.21 In the most recent Cochrane review of low-risk pregnant people (N = 34 randomized controlled trials with participants mostly in high-income settings) comparing induction of labor at 41 completed weeks’ gestation with expectant management,19 induction of labor was associated with fewer neonatal intensive care unit admissions, perinatal deaths, stillbirths, and cesarean births (Table 1), but little difference in perineal trauma, postpartum hemorrhage, neonatal encephalopathy, or neonatal trauma. Among their main outcomes (perinatal death, stillbirth, NICU admission, cesarean birth, operative vaginal birth, and perineal trauma), they saw no difference by parity, timing of induction, or the degree of cervical readiness. They estimated that 544 inductions at term would need to be conducted to prevent one perinatal death.

Table 1.

Risks and Benefits of Optimally Performed Elective Induction of Labor Compared With Expectant Management for Low-Risk Term Persons19

OutcomesNo. of Participants (No. of Studies Included in Review)Risk of Outcome per 1000 Pregnant People (95% CI)
With Expectant ManagementaWith Elective Induction of Labor After 39 0/7 wkGRADE Quality of Evidencec
Pregnant Person
Operative vaginal birth18,584 (22)136140
(131–150)		Moderate
Cesarean birth21,030 (31)186167
(158–177)		Moderate
Perineal traumad11,589 (5)3133
(26–39)		Low
Postpartum hemorrhagee12,609 (9)7981
(73–91)		Moderate
Neonate
Perinatal deathf18,795 (22)30.4
(0.1–1.9)		High
Stillbirthg18,795 (22)21
(0.15–1.5)		High
NICU admissionh17,826 (17)9583
(80–91)		High
Neonatal traumai13,106 (5)77
(5–12)		Moderate
Apgar score <7 at 5 mink18,345 (20)1310
(7–12)		Moderate

Abbreviations: GRADE, Grading of Recommendations, Assessment, Development and Evaluation; NICU, neonatal intensive care unit; NR, not reported; RR, relative risk.

a

Gestational age at which expectant management continued varied per study: for 10 trials, there was no gestational age limit for induction, whereas in the remaining 24 trials, labor was induced in women at 40 weeks’ gestation or beyond (range up to 44 weeks’ gestation in 4 older trials).

b

Gestational age at which induction of labor occurred varied per study, with induction of labor at less than 40 weeks’ gestation (8 trials), induction of labor between 40–41 weeks (6 trials), and induction of labor at greater than or equal to 41 weeks’ gestation (20 trials). Induction of labor protocols varied in each trial.

c

GRADE score108 as assessed by systematic review authors.

d

Describes sphincter laceration, severe perineal injury, third or fourth degree perineal tear, or third degree tear as defined differently by included trials.

e

Various cutoffs used, as outlined by included trials.

f

Includes intrauterine death plus neonatal deaths occurring in the first week of life.

g

Subset of perinatal deaths.

h

Admission to NICU for any amount of time.

i

Neonatal trauma defined differently by included trials; ranges from nerve injury to fractured clavicle, cephalic or intracerebral hematoma, to peripheral nerve injury, spinal cord trauma, and bone fracture.

Source information: Middleton et al 2020 Cochrane review of randomized controlled trials comparing induction of labor with expectant management in low-risk women of different parities at or beyond term gestation.19

Little is known about the longer-term outcomes of labor induction, including breastfeeding and parental-neonate attachment. Although immediate breastfeeding rates do not appear to be affected by induction compared with those for expectant management,19 researchers have not always examined the influence of breastfeeding intentions in these relationships. There is recent evidence from a large cohort of children in New York State (N = 5868 followed from 4 until 36 months of age with 7 administrations of the Ages and Stages Questionnaire to identify early childhood developmental delays) that greater gestational ages at birth were associated with lower odds of developmental delays after accounting for the influence of sociodemographic factors and maternal smoking.22 Of note, those researchers found that children born at 40 and 41 weeks’ gestation exhibited lower risks of developmental delay than did those born at 39 weeks (adjusted odds ratio at 40 weeks, 0.73 [95% CI, 0.55–0.96]; and at 41 weeks, 0.51 [95% CI, 0.32–0.82]). In another recent study,23 a longitudinal, population-based birth cohort study of 3079 children living in the Netherlands, researchers found that greater gestational ages at birth were associated with larger brain volumes on neuroimaging scans at 10 years of age. Similar to the New York study, these researchers saw benefits of gestational ages beyond 39 weeks. There is also observational evidence that induction of labor is associated with increased risk for perinatal mood disorders,24 but no high-quality studies have been published on this topic or on a person’s experience of labor induction, including the extent to which health care coercion and birth trauma differ in clients according to their mode of labor onset.

The health care costs associated with induction of labor are also an important consideration, as researchers in 2 multisite clinical trials of term elective induction found a net cost savings when the entire perinatal course was considered for participants who were electively induced compared with those who received expectant management.25,26 However, researchers using a theoretical cohort of 1.6 million healthy, nulliparous persons found that the cost-effectiveness of labor induction hinged upon differences in the cesarean birth rates between those whose labor was induced and those who were expectantly managed.27 For example, they saw cost savings if the induced cohort’s cesarean birth rate was 19% compared with 22% in the expectantly managed cohort. However, when the 2 groups had the same cesarean birth rate of 22%, a labor induction policy was no longer cost-effective. This means that if there is a widespread increase in elective induction at term before significant progress is made on increasing the success of labor induction, increases in cesarean birth and in the cost of birth-related health care might occur.

Currently, there is disagreement among US professional organizations regarding the routine use of elective labor induction. Although the American College of Nurse-Midwives (ACNM) discourages induction of labor without medical indication,28 the American College of Obstetricians and Gynecologists and Society for Maternal-Fetal Medicine support elective induction of labor for low-risk nulliparous women at 39 weeks’ gestation.29,30 Amid these disagreements, many pregnant persons desire to labor without medical intervention. The reasons for this reluctance are multifold. Most medical interventions in labor require continuous fetal heart rate monitoring, which can restrict laboring persons’ freedom of movement during labor.31 In addition, clinicians in many health care systems restrict oral intake for clients using medications like oxytocin during labor. Finally, induction of labor is a complex process. There are wide variations in rates of cesarean birth in laboring persons by hospital32 and individual health care provider33 that are independent of an individual client’s risk status.

When pregnant persons do not trust the health care system or do not feel confident that their health care provider will be successful in helping them achieve a safe vaginal birth, they may prefer to avoid medical intervention as much as possible.34,35 In the World Health Organization’s framework for quality maternal and newborn health care, evidence-based care provision and client’s experiences of care are held as equally important. Thus, this Clinical Bulletin providing guidance on the use of labor induction focuses on ways that clinicians can support person-centered decision-making around labor onset and use evidence-based approaches to induction of labor that support optimal perinatal outcomes and a positive childbirth experience.

Shared Decision-Making for Induction of Labor

Despite strong and widespread evidence-based clinical practice recommendations advocating for the inclusion of clients’ unique needs, preferences, and values in decision-making for labor and birth,36,37 recent research has shown that many persons report not being involved in decision-making nor receiving the support and information they felt was necessary to make informed choices about induction of labor.34,38–40 The current lack of person-centered care and informed decision-making for induction of labor negatively affects quality of care and client satisfaction38,41 and may exacerbate existing racially based health disparities.42,43

Given these findings and in the absence of consensus on evidence-based indications for and methods of inducing labor, health care providers are strongly encouraged to use a shared decision-making approach when discussing induction of labor with pregnant persons and their families.44 Detailed guidance on shared decision-making in general practice is available.36,45 For induction of labor, shared decision-making should be individualized but include the following essential components:

  • Assessment of clients’ desired level of involvement in decision-making about labor and ability to make decisions voluntarily.

  • Encouragement of active participation and bidirectional communication between the client and health care provider.

  • Provision of current evidence-based information regarding the strength and quality of health care provider recommendations for induction of labor.

  • Medically indicated induction of labor: if a person meets medical indications for labor induction, the midwife has a professional responsibility to recommend this course of action and help the person weigh their options.46

  • Elective induction of labor: discussion of elective induction of labor risks and benefits should use the latest evidence comparing expectant management with elective labor induction, and absolute numbers rather than relative odds should be quoted to aid in the client’s understanding (Table 1).

  • Sharing of practice-specific induction of labor outcome statistics, including rates of failed induction and other labor outcomes, for other clients with similar indications for induction of labor (eg, hypertensive issues, postterm gestation). Given evidence showing significant variation in cesarean birth rates from practice to practice,32 shared decision-making for induction of labor is best conducted with giving attention to practice-specific metrics.

  • Development of a structured process to document clients’ refusal of recommended induction of labor which preserves communication and continuity of pregnancy care.47

  • Sharing of detailed information with a client about the labor induction process and implications for their experience of labor and birth, including treatment alternatives.

Additional research into clinician communication, client education materials, use of decision aids, and other interventions is warranted to improve shared decision-making for labor induction.48

Induction of Labor Strategies Supporting Positive Childbirth Experiences

In 2018, the World Health Organization issued a report outlining numerous recommendations for intrapartum care to support a positive childbirth experience.35 These recommendations include freedom of mobility, oral intake, and avoidance of intravenous fluids, all of which are more difficult during labor induction in many US health care systems. Persons being induced may also have limited access to physiologic labor interventions such as ambulation, hydrotherapy, and alternative positioning.49 Based on US practices, induction of labor may not be a desirable option for those persons who prioritize a physiologic or low-intervention birth experience.50,51 It is thus crucial that clinicians offer induction of labor options that support positive childbirth experiences in keeping with individual goals. Once shared decision-making processes are used to identify the pregnant person’s goals, they can be integrated into the plan for inducing labor. Following are recommendations for inducing labor that have been shown to support high-quality and satisfying experiences of care.

Considerations for Practice

1. Given recent evidence of reduced rates of cesarean birth associated with elective induction of labor after 38 6/7 weeks’ gestation, how should I discuss induction of labor with my clients during shared decision-making conversations?

In persons without comorbidities or fetal conditions that would indicate a need for induction of labor, the risks and benefits of elective induction of labor at term gestation (39 0/7 to 41 6/7 weeks’ gestation) compared to expectant management should be considered within a person-centered perspective. Risks and benefits are best discussed in terms of absolute numbers to aid in the understanding of the pregnant person and their family members/support persons (Table 1). This discussion should include the increased duration of early labor following induction,52 the risks associated with the use of mechanical and pharmacological methods used to ripen the cervix and stimulate contractions, and the rates of cesarean birth both overall and following elective induction of labor, at the institution and practice levels. Methods that may decrease the risk of cesarean birth should also be discussed, including continuous labor support with a trained health care provider53 and upright positions or movement during the first stage of labor.54 Finally, the midwife should document the content and decisions made by the client in the medical record. From a risk management lens, this documentation should include specific fears or concerns expressed by the client and how they were addressed; current problems or diagnoses; pertinent medical, obstetric, or social history; fetal status; and the plan of care based on the discussion.55

2. When caring for persons who are trying to avoid induction of labor for postterm gestation, what is the evidence on ways to encourage spontaneous labor onset?

Many persons use nonmedical interventions in an attempt to induce labor, but not all interventions have good evidence supporting their use. Although commonly believed to cause spontaneous labor, sexual intercourse at term was not associated with an increased incidence of spontaneous labor in a meta-analysis of 3 randomized controlled trials.56 In contrast, breast or nipple stimulation, such as nipple rolling, breast massage, or use of a breast pump, stimulates oxytocin release and may therefore encourage spontaneous labor.57,58 However, more research is needed about the safety and efficacy of various forms of breast stimulation to guide clinical practice recommendations. Sweeping (or stripping) amniotic membranes from the lower uterine segment through digital cervical manipulation promotes the release of prostaglandins and encourages cervical effacement and dilation.59 In the absence of contraindications, this method has been shown to be generally safe and effective at reducing the likelihood of labor induction at postterm gestation.60,61 Additional research is needed to determine the optimal timing and frequency of membrane sweeping to promote labor onset.59

3. What is the process for outpatient cervical ripening?

Outpatient cervical ripening is primarily an option for healthy persons with term, singleton pregnancies.62 Cervical balloons are the primary cervical ripening method used in outpatient settings, although prostaglandins have also been used in some outpatient settings.63–65 The process begins with a nonstress test and administration of the cervical ripening agent, after which the person is monitored for evidence of a reassuring fetal heart rate pattern without uterine tachysystole or other complications and then discharged to home. Often, persons will return in the morning after overnight ripening or with onset of labor. Sample protocols for the use of misoprostol or Foley catheters as outpatient cervical ripening agents are available online at ACNM’sBirthtools.org website.66

4. When performing an induction of labor, what interventions allow women the most freedom to eat or move?

Policies regarding eating and drinking during labor vary across the United States and are related to concerns of aspiration in pregnant persons receiving anesthesia, a phenomenon known as Mendelson syndrome.67 However, aspiration is exceedingly rare and has been estimated to occur in approximately 0.001 indivdiduals per 1000 births for persons undergoing general anesthesia and in 3.8 per million women who receive regional anesthesia.68 Moreover, there may be benefits to oral intake on shortened labor duration. In a 2017 systematic review and meta-analysis of 10 trials (N = 3982) evaluating low-risk women, less-restrictive food intake, primarily with liquids, was associated with shortened duration of labor without other harms or benefits identified.69 Pregnant persons with additional risk factors for aspiration, including obesity, gestational diabetes mellitus, airways predicted to make intuabation difficult, or increased risk for operative birth, may benefit from restrictions to oral intake regardless of their induction of labor status or method, based on expert opinion from the American Society of Anesthesiologists.70 As recent research has shown that induction of labor itself does not increase the risk of operative birth,19,71 oral intake recommendations should be based on other risk factors.

To support a laboring person’s mobility and oral intake, nonpharmacologic cervical ripening options, like transcervical catheters (cervical balloons), might be substituted for prostaglandin cervical ripening methods. A key benefit of transcervical catheters compared to prostaglandins for cervical ripening is their localized action with few systemic adverse effects.72 For this reason, transcervical catheters are the primary cervical ripening method used in outpatient settings.72 For persons needing induction of labor whose cervical dilatation is 4 or more centimeters, amniotomy may encourage labor without the need for continuous fetal monitoring or restrictions in movement, absent other maternal or fetal complications.73

When promoting mobility during induction of labor, the equipment available for continuous fetal heart rate monitoring is also an important consideration. Wireless fetal heart rate monitors and Bluetooth monitoring devices can facilitate various position changes and support the use of hydrotherapy.74 Telemetry units use the same ultrasound Doppler and tocodynamometer as traditional units do, whereas Bluetooth devices use wireless patches to transmit cardiotocographic and uterine contraction information.75

5. What if the person’s cervix is closed and does not open in response to prostaglandins? What is the next step for induction of labor?

Persons choosing elective induction at term, or those who are being induced for a medical indication that is stable and are eligible for expectant management, may be discharged home if there is no response to induction methods and no indication for ongoing surveillance. No specific studies are available regarding outcomes for persons who were discharged following nonresponse to cervical ripening methods, but this is an alternative that can be explored using shared decision-making.

If the decision is made to continue with induction of labor in the situation of a closed cervix following prostaglandin treatment, care should be taken that the optimal dose and type of prostaglandins are being used. There are 2 types of prostaglandins used for cervical ripening in the United States: misoprostol, a prostaglandin E1 analogue, and dinoprostone, a prostaglandin E2 analogue. Misoprostol appears to initiate labor over a shorter duration than does dinoprostone without a difference in rates of cesarean birth, uterine hyperstimulation, or the incidence of meconium-stained amniotic fluid.76 No trials have specified a maximum number of doses of dinoprostone that can be used in the situation of a persistently closed cervix. However, in randomized control trials, misoprostol was administered via oral, buccal, or vaginal route at doses of 25 to 50 mcg every 4 hours, for a maximum of 4 to 7 doses without significant difference in perinatal outcomes or adverse effects.77,78

If there is an ongoing medical indication for induction of labor and the cervix has not responded significantly to the maximum doses of prostaglandin, introduction of a transcervical catheter may be helpful. Double-lumen balloon catheters are equipped with a stylet to guide insertion, which is possible even through a closed cervix once softening has occurred. Insertion can be accomplished either digitally or with visualization using a speculum.79 The use of a speculum and stylet may be particularly helpful if the cervical dilatation is minimal. Initiation of a low-dose oxytocin infusion or insertion of an osmotic dilator device can also be considered if there is no response to prostaglandins or if a balloon cathether is unable to be inserted. However, when the Bishop score is less than 4, early use of oxytocin as a solo agent has been identified as a significant independent risk factor for cesarean birth.78 Therefore, whenever possible, prostaglandins and/or transcervical catheters should be used rather than oxytocin during labor induction when persons have an unripe cervix.

6. How long should I continue to use cervical ripening methods during induction of labor before starting synthetic oxytocin to initiate active labor?

The newest evidence suggests that cervical ripening should continue until a person’s Bishop score is at least 6 if they are multiparous and at least 8 if they are nulliparous.80 Although this may take several days, especially in nulliparous persons, early initiation of synthetic oxytocin, especially when a Bishop score is less than 4, is associated with increased risk of cesarean birth.78 Maternal and fetal risks of synthetic oxytocin administration have been shown to be dose dependent and are variably related to the expression and concentration of oxytocin receptors in each person’s uterus.81 However, prolonged activation of oxytocin receptors is known to cause desensitization, thereby decreasing the ability of the uterus to contract. Clinically, this change can increase the risk of postpartum hemorrhage.82 For example, in a 2020 retrospective cross-sectional analysis of the Consortium for Safe Labor data, oxytocin infusion lasting longer than 7 hours during induction of labor increased the odds of a postpartum hemorrhage in healthy laboring persons who had vaginal births. In other research, exposure to an oxytocin rate of 20 milliunits per minute for more than 4 hours increased the odds of severe postpartum hemorrhage by 1.62 (95% CI, 1.05–2.57).83

7. What is the evidence on the use of amniotomy during induction of labor?

Amniotomy appears to be most effective for increasing uterine activity and reducing the cesarean birth rate during induction of labor when the cervix is dilated at to at least 4 centimeters,73,84 although recent evidence from a meta-analysis (N = 1273 in 4 trials) supported amniotomy as early as 3 centimeters cervical dilatation following cervical ripening as a safe and effective method of hastening induction of labor.85

8. What is the evidence on turning off synthetic oxytocin infusions after active labor is established to give women more freedom to move during contractions?

Once active labor is established, discontinuing oxytocin is associated with reduced risks of both cesarean birth and uterine tachysystole with fetal heart rate changes.86 In clients who discontinue oxytocin infusions during active labor, 70% continued labor successfully without additional oxytocin infusion in a meta-analysis of 9 trials (N = 1538 births).87 If oxytocin infusion is discontinued during induction of labor, intermittent auscultation is recommended for persons with low-risk pregnancies.88 A period of 30 to 60 minutes of continuous electronic fetal monitoring following discontinuation of the oxytocin infusion would be appropriate before initiating intermittent auscultation, based on its pharmacokinetic properties.55

9. When should an induction be stopped?

The length of labor induction is dependent on a variety of factors, including the Bishop score, the choice of induction interventions, and the maternal body mass index.89,90 The first stage of induced labor progresses over a much longer period than does spontaneous labor, with the median (95th percentile) time being 5.5 (16.8) hours for induced labor versus 3.8 (11.8) hours for spontaneous labor in nulliparous persons and 4.4 (16.2) hours for induced labor in multiparous persons versus 2.4 (8.8) hours for spontaneous labor in a retrospective cohort study (N = 5388 labors) of pregnant people admitted for labor at 37 weeks’ or more gestation who reached the second stage of labor.52 There is recent literature supporting the continuation of labor induction through at least 15 hours of latent-phase labor (defined as the period of induction that follows successful cervical ripening when amniotomy is performed and oxytocin infusion is initiated and lasting until the cervix reaches 5 cm dilatation).91,92 During active labor, defined as starting at 5 to 6 centimeters cervical dilatation or more in the presence of regular contractions causing progressive cervical change, the same guidelines as those for physiologic labor progress apply.93 If uterine activity is inadequate based on Montevideo units during the active phase, an arrest of labor should not be diagnosed before 6 hours without cervical change. If contractions are adequate, no cervical change over 4 hours may be indicative of an arrest of labor. As in spontaneous labor, membrane status, fetal presentation, fetal descent, and environmental factors are important to assess and provide support for labor progress.

10. What are the safest ways to induce labor in persons with a uterine scar who desire a vaginal birth after cesarean?

Transcervical catheters offer a safe, nonpharmacologic option for persons who require induction of labor and desire a trial of labor after cesarean.94 Synthetic oxytocin and osmotic dilator devices may also be used for cervical ripening and to stimulate uterine contractions in these persons.94 In a small trial comparing cervical ripening methods for people with a previous cesarean birth and low Bishop score, French investigators found that the balloon catheter was associated with a higher probability of vaginal birth than low-dose intravenous oxytocin.95

11. How should induction of labor techniques be adapted when caring for pregnant persons who are obese?

Persons with obesity more often end induction of labor with an unplanned cesarean birth than do persons with lower body mass index.96 The primary reason for this disparity in the use of cesarean birth in people with obesity who are induced is that they require more time for induction of labor than do persons of lower weights.97 For example, in a retrospective multicenter cohort study (N = 2122 labor inductions), the mean induction to birth interval was 31.65 hours for women with obesity category III, 29.08 hours for women with obesity category II, and 27.81 hours for women with obesity category I, compared with 25.8 hours for women in normal-weight category.97 In addition, there is observational evidence that persons with obesity appear to complete cervical ripening more effectively when dosed with misoprostol than with dinoprostone, and they have lower rates of cesarean birth when using misoprostol.98 There is also observational evidence that the higher a person’s body mass index, the lower their uterine response will be to amniotomy at any cervical dilation.99 Induction of labor timelines and the initiation of interventions like amniotomy and oxytocin should therefore be individualized based on a person’s body mass index.

12. What complementary and alternative therapies are effective for induction of labor?

Despite its long history of use for inducing onset of spontaneous labor, castor oil has minimal evidence to support its efficacy and is commonly associated with adverse effects of nausea, vomiting, and diarrhea.100 However, in a small trial, castor oil appeared to be effective for induction of labor in outpatient settings among multiparous persons without obstetric complications.101 In research on other herbal therapies for cervical ripening or labor initiation, such as red raspberry leaf, evening primrose oil, and black or blue cohosh, investigators found that there was insufficient quality data to draw conclusions about the efficacy of these methods and raised numerous concerns about their safety.102,103 Persons may also seek out acupuncture or acupressure to induce labor onset. Limited evidence suggests that these techniques appear to be safe and that acupuncture may be effective at reducing the need for cervical ripening.104 Additional research is needed before evidence-based clinical recommendations can be made regarding the use of complementary and alternative therapies for induction of labor.

Implications for Research

Research on induction of labor is needed in both the clinical and research sectors, as described below:

  • Quality improvement tracking of labor induction success is needed. In many health care systems, health care provider performance related to induction of labor is not monitored. However, persons have a right to be informed of their chances of successfully achieving vaginal birth and other pregnancy outcomes in each birth setting before consenting to the procedure. Therefore, all practices should track key induction of labor outcomes for clients with the same induction indication, in addition to their other clinical tracking.Table 2 provides a list of baseline induction of labor statistics that should be tracked, along with their rates in trial participants experiencing elective induction of labor versus expectant management. Similar comparisons of outcome statistics for pregnant clients with medical indications for labor induction are also available for health care providers caring for pregnant persons with these comorbidities (eg, hypertension,13 postterm pregnancy,105 premature rupture of membranes at term gestation,106 advanced maternal age,6 and maternal diabetes107).

  • More research is needed on the interactions between health care providers and clients around induction of labor decision-making, including a specific focus on how these interactions might be different for those who are members of racial or ethnic minorities, are from vulnerable populations, or have risk factors such as obesity.

  • More research is needed to understand if the disruption of physiologic processes during induced labor might have implications for both short- and longer-term health of women and their infants.

  • Research is needed on the safety and efficacy of herbal and homeopathic uterotonics, nipple stimulation, and other complementary and alternative health approaches to induce labor.

  • More research is needed comparing the effectiveness of different labor induction protocols on maternal and neonatal outcomes, including those that incorporate outpatient cervical ripening, midwife-supported induction of labor, and individualization based on specific client risk factors such as obesity.

  • Finally, more research is needed to examine the processes and outcomes of person-centered induction of labor protocols that incorporate hydrotherapy, ambulation, oral nutrition, and other physiologic labor practices.

Table 2.

Quality Improvement Targets for Induction of Labor in Pregnant People at Low Risk for Complications

Quality Improvement TargetDefinitionTarget Rate From ARRIVE Triala (N = 3059 People Induced), %Target Rate From Cochrane Meta-Analysisb (No. of People Varies by Outcome), %
Cesarean birth following induction of laborCesarean birth following induction of labor in a person without maternal or fetal conditions indicating this mode of birth at 39 weeks’ gestation18.616.3
Operative vaginal birthForceps or vacuum-assisted vaginal birth8.520.6
Perineal traumaThird or fourth degree perineal laceration3.41.9
Postpartum
hemorrhage		Hemorrhage from birth until hospital discharge requiring transfusion, nonelective hysterectomy, use of 2 or more uterotonics (other than oxytocin), curettage, or other surgical interventions54.65.1
Neonatal admission to NICUAdmission to the NICU or
intermediate-care unit of infants from birth until hospital discharge.5,19		11.77.5
Perinatal deathIntrauterine death plus neonatal deaths in the first week of life.19 Antepartum stillbirth, intrapartum stillbirth, and neonatal death50.10.04

Abbreviations: ARRIVE, A Randomized Trial of Induction Versus Expectant Management; NICU, neonatal intensive care unit.

a

Rate of each outcome among nulliparous women in the ARRIVE trial5 who were randomized to the induction arm. Induction of labor occurred from 39 0/7 weeks’ gestation to 39 4/7 weeks’ gestation and included cervical ripening if modified Bishop score was less than 5 followed by latent-phase labor of at least 12 hours after completion of ripening, rupture of membranes, and initiation of oxytocin infusion.

b

Rate of each outcome among pregnant people of mixed parity included in studies reviewed in systematic review and meta analysis19 comparing induction of labor with expectant management among pregnant people at low risk for complications. Gestational age at which induction of labor occurred varied per study, with induction of labor at less than 40 weeks’ gestation (8 trials), induction of labor between 40–41 weeks (6 trials), and induction of labor at greater than or equal to 41 weeks’ gestation (20 trials). Induction of labor protocols varied in each trial.

ACKNOWLEDGMENTS

ACNM acknowledges with thanks the contributions of contributing reviewers Tekoa King and Elise Erickson.

This Clinical Bulletin was developed under the direction of the Clinical Practice and Documents Section of the Division of Standards and Practice of the American College of Nurse-Midwives as an educational aid for midwives. This Clinical Bulletin is presented ‘as is’ without a warranty of any kind and is not intended to dictate a course of management or to substitute for individual professional judgment. It is intended to identify recognized or emerging methods and techniques for clinical practice that midwives may consider incorporating into their practices. The needs of an individual patient or the resources and limitations of an institution or type of practice may call for variations or other aspects of clinical care.

Footnotes

CONFLICT OF INTEREST

The authors declare no conflicts of interest.

REFERENCES

  • 1.Menard MK, Main EK, Currigan SM. Executive summary of the reVITALize initiative: standardizing obstetric data definitions. Obstet Gynecol. 2014;124(1):150–153. [DOI] [PubMed] [Google Scholar]
  • 2.Martin JA, Hamilton BE, Osterman MJ, Driscoll AK. Births: Final Data for 2018. Centers for Disease Control and Prevention National Center for Health Statistics. 2019. [PubMed] [Google Scholar]
  • 3.Driscoll AK, Gregory CW. Increases in Prepregnancy Obesity: United States, 2016–2019. US Department of Health and Human Services. November2020. [PubMed] [Google Scholar]
  • 4.Centers for Disease Control and Prevention Division of Reproductive Health. Hypertensive disorders in pregnancy, 1993–2014. US Department of Health and Human Services. Updated February 28, 2019.https://www.cdc.gov/reproductivehealth/maternalinfanthealth/pregnancy-complications-data.htm#hyper [Google Scholar]
  • 5.Grobman WA, Rice MM, Reddy UM, et al. Labor induction versus expectant management in low-risk nulliparous women. N Engl J Med. 2018;379(6):513–523. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Walker KF, Bugg GJ, Macpherson M, et al. Randomized trial of labor induction in women 35 years of age or older. N Engl J Med. 2016;374(9):813–822. [DOI] [PubMed] [Google Scholar]
  • 7.American College of Nurse-Midwives. Core competencies for basic midwifery practice. American College of Nurse-Midwives. March20, 2020.https://www.midwife.org/acnm/files/acnmlibrarydata/uploadfilename/000000000050/ACNMCoreCompetenciesMar2020_final.pdf
  • 8.Martin JA, Hamilton BE, Osterman MJ, Curtin SC, Matthews TJ. Births: final data for 2012. Natl Vital Stat Rep. 2013;62(9):1–68. [PubMed] [Google Scholar]
  • 9.Oshiro BT, Kowalewski L, Sappenfield W, et al. A multistate quality improvement program to decrease elective deliveries before 39 weeks of gestation. Obstet Gynecol. 2013;121(5):1025–1031. [DOI] [PubMed] [Google Scholar]
  • 10.American College of Obstetricians and Gynecologists. ACOG Committee opinion No. 579: definition of term pregnancy. Obstet Gynecol. 2013;122(5):1139–1140. [DOI] [PubMed] [Google Scholar]
  • 11.Bingham D, Ruhl C, Cockey CD. Don’t rush me … go the full 40: AWHONN’s public health campaign promotes spontaneous labor and normal birth to reduce overuse of inductions and cesareans. J Perinat Educ. 2013;22(4):189–193. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 12.Osterman MJ, Martin JA. Recent declines in induction of labor by gestational age. NCHS Data Brief. 2014;(155):1–8. [PubMed] [Google Scholar]
  • 13.Koopmans CM, Bijlenga D, Groen H, et al. Induction of labour versus expectant monitoring for gestational hypertension or mild preeclampsia after 36 weeks’ gestation (HYPITAT): a multicentre, open-label randomised controlled trial. Lancet. 2009;374(9694):979–988. [DOI] [PubMed] [Google Scholar]
  • 14.American College of Obstetricians and Gynecologists. ACOG practice bulletin No. 107: induction of labor. Obstet Gynecol. 2009;114(2Pt 1):386–397. [DOI] [PubMed] [Google Scholar]
  • 15.American College of Obstetricians and Gynecologists. Practice bulletin No. 146: management of late-term and postterm pregnancies. Obstet Gynecol. 2014;124(2 Pt 1):390–396. [DOI] [PubMed] [Google Scholar]
  • 16.Ehrenthal DB, Jiang X, Strobino DM. Labor induction and the risk of a cesarean delivery among nulliparous women at term. Obstet Gynecol. 2010;116(1):35–42. [DOI] [PubMed] [Google Scholar]
  • 17.Caughey AB, Sundaram V, Kaimal AJ, et al. Maternal and neonatal outcomes of elective induction of labor. Evid Rep Technol Assess (Full Rep). 2009;(176):1–257. [PMC free article] [PubMed] [Google Scholar]
  • 18.Saccone G, Berghella V. Induction of labor at full term in uncomplicated singleton gestations: a systematic review and metaanalysis of randomized controlled trials. Am J Obstet Gynecol. 2015;213(5):629–636. [DOI] [PubMed] [Google Scholar]
  • 19.Middleton P, Shepherd E, Morris J, Crowther CA, Gomersall JC. Induction of labour at or beyond 37 weeks’ gestation. Cochrane Database Syst Rev. 2020;7(7):CD004945. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 20.Erickson EN, Bailey JM, Colo SD, Carlson NS, Tilden EL. Induction of labor or expectant management? Birth outcomes for nulliparous individuals choosing midwifery care [published online ahead of print, 2021 May 28]. Birth. 2021; 10.1111/birt.12560. 10.1111/birt.12560 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 21.Grobman W. A randomized trial of elective induction of labor at 39 weeks compared with expectant management of low-risk nulliparous women. Am J Obstet Gynecol. 2018;218(Suppl 1):S601. [Google Scholar]
  • 22.Hochstedler KA, Bell G, Park H, et al. Gestational age at birth and risk of developmental delay: the Upstate KIDS Study. Am J Perinatol. 2021;38(10):1088–1095. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 23.El Marroun H, Zou R, Leeuwenburg MF, et al. Association of gestational age at birth with brain morphometry. JAMA Pediatr. 2020;174(12):1149–1158. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 24.Smorti M, Ponti L, Pancetti F. A comprehensive analysis of postpartum depression risk factors: the role of socio-demographic, individual, relational, and delivery characteristics. Front Public Health. 2019;7:295. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 25.Walker KF, Dritsaki M, Bugg G, et al. Labour induction near term for women aged 35 or over: an economic evaluation. BJOG. 2017;124(6):929–934. [DOI] [PubMed] [Google Scholar]
  • 26.Grobman WA, Sandoval G, Reddy UM, et al. Health resource utilization of labor induction versus expectant management. Am J Obstet Gynecol. 2020;222(4):369.e1–369.e11. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 27.Hersh AR, Skeith AE, Sargent JA, Caughey AB. Induction of labor at 39 weeks of gestation versus expectant management for low-risk nulliparous women: a cost-effectiveness analysis. Am J Obstet Gynecol. 2019;220(6):590.e1–590.e10. [DOI] [PubMed] [Google Scholar]
  • 28.American College of Nurse-Midwives. Position Statement: Induction of Labor. American College of Nurse-Midwives. Revised September 2016.https://www.midwife.org/acnm/files/ACNMLibraryData/UPLOADFILENAME/000000000235/Induction-of-Labor-2016.pdf
  • 29.American College of Obstetricians and Gynecologists, Society for Maternal Fetal Medicine. Clinical guidance for integration of the findings of the ARRIVE trial: labor induction versus expectant management in low-risk nulliparous women. August2018.https://www.acog.org/clinical/clinical-guidance/practice-advisory/articles/2018/08/clinical-guidance-for-integration-of-the-findings-of-the-arrive-trial
  • 30.Society of Maternal-Fetal (SMFM) Publications Committee. SMFM statement on elective induction of labor in low-risk nulliparous women at term: the ARRIVE trial. Am J Obstet Gynecol. 2019;221(1):B2–B4. [DOI] [PubMed] [Google Scholar]
  • 31.American College of Obstetricians and Gynecologists. ACOG Committee opinion No. 766: approaches to limit intervention during labor and birth. Obstet Gynecol. 2019;133(2):e164–e173. [DOI] [PubMed] [Google Scholar]
  • 32.Pasko DN, McGee P, Grobman WA, et al. Variation in the nulliparous, term, singleton, vertex cesarean delivery rate. Obstet Gynecol. 2018;131(6):1039–1048. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 33.Attanasio L, Kozhimannil KB. Relationship between hospital-level percentage of midwife-attended births and obstetric procedure utilization. J Midwifery Womens Health. 2018;63(1):14–22. [DOI] [PubMed] [Google Scholar]
  • 34.Lou S, Hvidman L, Uldbjerg N, et al. Women‘s experiences of postterm induction of labor: a systematic review of qualitative studies. Birth. 2019;46(3):400–410. [DOI] [PubMed] [Google Scholar]
  • 35.World Health Organization. WHO Recommendations: Intrapartum Care for a Positive Childbirth Experience. 2018.http://apps.who.int/iris/bitstream/handle/10665/260178/9789241550215-eng.pdf?sequence=1 [PubMed]
  • 36.American College of Obstetricians and Gynecologists. Informed consent and shared decision making in obstetrics and gynecology: ACOG Committee opinion, number 819. Obstet Gynecol. 2021;137(2):e34–e41. [DOI] [PubMed] [Google Scholar]
  • 37.Agency for Healthcare Research and Quality. The SHARE approach. 2020.https://www.ahrq.gov/health-literacy/professionaltraining/shared-decision/index.html. [DOI] [PubMed]
  • 38.Coates D, Goodfellow A, Sinclair L. Induction of labour: experiences of care and decision-making of women and clinicians. Women Birth. 2020;33(1):e1–e14. [DOI] [PubMed] [Google Scholar]
  • 39.Lawrence HC III, Copel JA, O’Keeffe DF, et al. Quality client care in labor and delivery: a call to action. Am J Obstet Gynecol. 2012;207(3):147–148. [DOI] [PubMed] [Google Scholar]
  • 40.Declercq ER, Cheng ER, Sakala C. Does maternity care decision-making conform to shared decision- making standards for repeat cesarean and labor induction after suspected macrosomia?Birth. 2018;45(3):236–244. [DOI] [PubMed] [Google Scholar]
  • 41.Moore JE, Low LK, Titler MG, Dalton VK, Sampselle CM. Moving toward client-centered care: Women’s decisions, perceptions, and experiences of the induction of labor process. Birth. 2014;41(2):138–146. [DOI] [PubMed] [Google Scholar]
  • 42.Morton CH, Henley MM, Seacrist M, Roth LM. Bearing witness: United States and Canadian maternity support workers’ observations of disrespectful care in childbirth. Birth. 2018;45(3):263–274. [DOI] [PubMed] [Google Scholar]
  • 43.Attanasio LB, Kozhimannil KB, Kjerulff KH. Factors influencing women’s perceptions of shared decision making during labor and delivery: results from a large-scale cohort study of first childbirth. Client Educ Couns. 2018;101(6):1130–1136. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 44.McCormack J, Elwyn G. Shared decision is the only outcome that matters when it comes to evaluating evidence-based practice. BMJ Evid Based Med. 2018;23(4):137–139. [DOI] [PubMed] [Google Scholar]
  • 45.American College of Nurse-Midwives. Shared decision-making: resources and tools. American College of Nurse-Midwives. 2020.https://birthtools.org/Shared-Decision-Making-Toolbox. [Google Scholar]
  • 46.King TL, Likis FE, Wilson-Liverman AM. Shared decision making: misconstrued and misused. J Midwifery Womens Health. 2018;63(3):257–258. [DOI] [PubMed] [Google Scholar]
  • 47.Jenkinson B, Kruske S, Stapleton H, Beckmann M, Reynolds M, Kildea S. Women’s, midwives’ and obstetricians’ experiences of a structured process to document refusal of recommended maternity care. Women Birth. 2016;29(6):531–541. [DOI] [PubMed] [Google Scholar]
  • 48.Légaré F, Adekpedjou R, Stacey D, et al. Interventions for increasing the use of shared decision making by healthcare professionals. Cochrane Database Syst Rev. 2018;7(7):CD006732. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 49.Glantz JC. Elective induction vs. spontaneous labor associations and outcomes. J Reprod Med. 2005;50(4):235–240. [PubMed] [Google Scholar]
  • 50.Declercq E, Belanoff C, Iverson R. Maternal perceptions of the experience of attempted labor induction and medically elective inductions: analysis of survey results from listening to mothers in California. BMC Pregnancy Childbirth. 2020;20:458. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 51.Vedam S, Stoll K, Taiwo TK, et al. The Giving Voice to Mothers study: inequity and mistreatment during pregnancy and childbirth in the United States. Reprod Health. 2019;16(1):77. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 52.Harper LM, Caughey AB, Odibo AO, Roehl KA, Zhao Q, Cahill AG. Normal progress of induced labor. Obstet Gynecol. 2012;119(6):1113–1118. [DOI] [PubMed] [Google Scholar]
  • 53.Bohren MA, Hofmeyr GJ, Sakala C, Fukuzawa RK, Cuthbert A. Continuous support for women during childbirth. Cochrane Database Syst Rev. 2017;7(7):CD003766. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 54.Lawrence A, Lewis L, Hofmeyr GJ, Styles C. Maternal positions and mobility during first stage labour. Cochrane Database Syst Rev. 2013;(8):CD003934. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 55.Page K, McCool WF, Guidera M. Examination of the pharmacology of oxytocin and clinical guidelines for use in labor. J Midwifery Womens Health. 2017;62(4):425–433. [DOI] [PubMed] [Google Scholar]
  • 56.Carbone L, De Vivo V, Saccone G, et al. Sexual intercourse for induction of spontaneous onset of labor: a systematic review and metaanalysis of randomized controlled trials. J Sex Med. 2019;16(11):1787–1795. [DOI] [PubMed] [Google Scholar]
  • 57.Takahata K, Horiuchi S, Tadokoro Y, Sawano E, Shinohara K. Oxytocin levels in low-risk primiparas following breast stimulation for spontaneous onset of labor: a quasi-experimental study. BMC Pregnancy Childbirth. 2019;19(1):351. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 58.Kavanagh J, Kelly AJ, Thomas J. Breast stimulation for ripening and induction of labour. Cochrane Database Syst Rev. 2005;(3):CD003392. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 59.Finucane EM, Murphy DJ, Biesty LM, et al. Membrane sweeping for induction of labour. Cochrane Database Syst Rev. 2020;(2): CD000451. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 60.Heilman E, Sushereba E. Amniotic membrane sweeping. Semin Perinatol. 2015;39(6):466–470. [DOI] [PubMed] [Google Scholar]
  • 61.Avdiyovski H, Haith-Cooper M, Scally A. Membrane sweeping at term to promote spontaneous labour and reduce the likelihood of a formal induction of labour for postmaturity: a systematic review and meta-analysis. J Obstet Gynaecol. 2019;39(1):54–62. [DOI] [PubMed] [Google Scholar]
  • 62.Vogel JP, Osoti AO, Kelly AJ, Livio S, Norman JE, Alfirevic Z. Pharmacological and mechanical interventions for labour induction in outpatient settings. Cochrane Database Syst Rev. 2017;9(9):CD007701. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 63.Diederen M, Gommers J, Wilkinson C, Turnbull D, Mol B. Safety of the balloon catheter for cervical ripening in outclient care: complications during the period from insertion to expulsion of a balloon catheter in the process of labour induction: a systematic review. BJOG. 2018;125(9):1086–1095. [DOI] [PubMed] [Google Scholar]
  • 64.Levine LD, Downes KL, Elovitz MA, Parry S, Sammel MD, Srinivas SK. Mechanical and pharmacologic methods of labor induction: a randomized controlled trial. Obstet Gynecol. 2016;128(6):1357–1364. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 65.Leopold B, Sciscione A. Is there a place for outclient preinduction cervical ripening?Obstet Gynecol Clin North Am. 2017;44(4):583–591. [DOI] [PubMed] [Google Scholar]
  • 66.American College of Nurse-Midwives. BirthTOOLS.org: Tools for Optimizing the Outcomes of Labor Safely.https://www.birthtools.org/
  • 67.American College of Nurse-Midwives. Providing oral nutrition to women in labor: American College of Nurse-Midwives. J Midwifery Womens Health. 2016;61(4):528–534. [DOI] [PubMed] [Google Scholar]
  • 68.Scheepers HC, Essed GG, Brouns F. Aspects of food and fluid intake during labour. Policies of midwives and obstetricians in The Netherlands. Eur J Obstet Gynecol Reprod Biol. 1998;78(1):37–40. [DOI] [PubMed] [Google Scholar]
  • 69.Ciardulli A, Saccone G, Anastasio H, Berghella V. Less-restrictive food intake during labor in low-risk singleton pregnancies: a systematic review and meta-analysis. Obstet Gynecol. 2017;129(3):473–480. [DOI] [PubMed] [Google Scholar]
  • 70.Practice guidelines for obstetric anesthesia: an updated report by the American Society of Anesthesiologists Task Force on Obstetric Anesthesia and the Society for Obstetric Anesthesia and Perinatology. Anesthesiology. 2016;124(2):270–300. [DOI] [PubMed] [Google Scholar]
  • 71.Saccone G, Della Corte L, Maruotti GM, et al. Induction of labor at full-term in pregnant women with uncomplicated singleton pregnancy: a systematic review and meta-analysis of randomized trials. Acta Obstet Gynecol Scand. 2019;98(8):958–966. [DOI] [PubMed] [Google Scholar]
  • 72.Lajusticia H, Martinez-Dominguez SJ, Perez-Roncero GR, Chedraui P, Perez-Lopez FR. Single versus double-balloon catheters for the induction of labor of singleton pregnancies: a meta-analysis of randomized and quasi-randomized controlled trials. Arch Gynecol Obstet. 2018;297(5):1089–1100. [DOI] [PubMed] [Google Scholar]
  • 73.Battarbee AN, Glover AV, Stamilio DM. Association between early amniotomy in labour induction and severe maternal and neonatal morbidity. Aust N Z J Obstet Gynaecol. 2020;60(1):108–114. [DOI] [PubMed] [Google Scholar]
  • 74.Panelli D, Teplick F, McCarthy M, Hebert S. Comparing methods to secure external fetal-monitoring devices. MCN Am J Matern Child Nurs. 2014;39(1):41–47; quiz 48–49. [DOI] [PubMed] [Google Scholar]
  • 75.Monson M, Heuser C, Einerson BD, et al. Evaluation of an external fetal electrocardiogram monitoring system: a randomized controlled trial. Am J Obstet Gynecol. 2020;223(2):244.e1–244.e12. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 76.Benalcazar-Parra C, Monfort-Orti R, Ye-Lin Y, et al. Comparison of labour induction with misoprostol and dinoprostone and characterization of uterine response based on electrohysterogram. J Matern Fetal Med. 2019;32(10):1586–1594. [DOI] [PubMed] [Google Scholar]
  • 77.Rouzi AA, Alsahly N, Alamoudi R, et al. Randomized clinical trial between hourly titrated and 2 hourly static oral misoprostol solution for induction of labor. Am J Obstet Gynecol. 2017;216(4):405.e1–405.e6. [DOI] [PubMed] [Google Scholar]
  • 78.Pimentel VM, Arabkhazaeli M, Moon JY, et al. Induction of labor using one dose vs multiple doses of misoprostol: a randomized controlled trial. Am J Obstet Gynecol. 2018;218(6):614.e1–614.e8. [DOI] [PubMed] [Google Scholar]
  • 79.Chia HM, Tan PC, Tan SP, Hamdan M, Omar SZ. Speculum versus digital insertion of Foley catheter for induction of labor in nulliparas with unripe cervix: a randomized controlled trial. BMC Pregnancy Childbirth. 2020;20(1):330. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 80.CMQCC. Appendix R: induction of labor algorithm. California Maternal Health Quality Care Collaborative; April23, 2019.https://www.cmqcc.org/resource/appendix-r-induction-labor-algorithm
  • 81.Blanks AM, Thornton S. The role of oxytocin in parturition. BJOG. 2003;110Suppl 20:46–51. [DOI] [PubMed] [Google Scholar]
  • 82.Erickson EN, Carlson NS. Predicting postpartum hemorrhage after low-risk vaginal birth by labor characteristics and oxytocin administration. Birth. 2020;49(6):549–563. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 83.Grotegut CA, Paglia MJ, Johnson LN, Thames B, James AH. Oxytocin exposure during labor among women with postpartum hemorrhage secondary to uterine atony. Am J Obstet Gynecol. 2011;204(1):56.e1–56.e6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 84.Bala A, Bagga R, Kalra J, Dutta S. Early versus delayed amniotomy during labor induction with oxytocin in women with Bishop’s score of ≥6: a randomized trial. J Matern Fetal Neonatal Med. 2018;31(22):2994–3001. [DOI] [PubMed] [Google Scholar]
  • 85.De Vivo V, Carbone L, Saccone G, et al. Early amniotomy after cervical ripening for induction of labor: a systematic review and meta-analysis of randomized controlled trials. Am J Obstet Gynecol. 2020;222(4):320–329. [DOI] [PubMed] [Google Scholar]
  • 86.Boie S, Glavind J, Velu AV, et al. Discontinuation of intravenous oxytocin in the active phase of induced labour. Cochrane Database Syst Rev. 2018;8(8):CD012274. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 87.Saccone G, Ciardulli A, Baxter JK, et al. Discontinuing oxytocin infusion in the active phase of labor: a systematic review and metaanalysis. Obstet Gynecol. 2017;130(5):1090–1096. [DOI] [PubMed] [Google Scholar]
  • 88.Association of Women’s Health, Obstetric, and Neonatal Nurses. AWHONN position statement: fetal heart monitoring. J Obstet Gynecol Neonatal Nurs. 2015;44(5):683–686. [Google Scholar]
  • 89.Carlhäll S, Källén K, Blomberg M. The effect of maternal body mass index on duration of induced labor. Acta Obstet Gynecol Scand. 2020;99(5):669–678. [DOI] [PubMed] [Google Scholar]
  • 90.Wollmann CL, Ahlberg M, Petersson G, Saltvedt S, Stephansson O. Time-to-delivery and delivery outcomes comparing three methods of labor induction in 7551 nulliparous women: a population-based cohort study. J Perinatol. 2017;37(11):1197–1203. [DOI] [PubMed] [Google Scholar]
  • 91.Schoen C, Navathe R. Failed induction of labor. Semin Perinatol. 2015;39(6):483–487. [DOI] [PubMed] [Google Scholar]
  • 92.Grobman WA, Bailit J, Lai Y, et al. Defining failed induction of labor. Am J Obstet Gynecol. 2018;218(1):122.e1–122.e8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 93.Spong CY, Berghella V, Wenstrom KD, Mercer BM, Saade GR. Preventing the first cesarean delivery: summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, and American College of Obstetricians and Gynecologists Workshop. Obstet Gynecol. 2012;120(5):1181–1193. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 94.American College of Obstetricians and Gynecologists. ACOG practice bulletin No. 205: vaginal birth after cesarean delivery. Obstet Gynecol. 2019;133(2):e110–e127. [DOI] [PubMed] [Google Scholar]
  • 95.Sarreau M, Isly H, Poulain P, et al. Balloon catheter vs oxytocin alone for induction of labor in women with a previous cesarean section: a randomized controlled trial. Acta Obstet Gynecol Scand. 2020;99(2):259–266. [DOI] [PubMed] [Google Scholar]
  • 96.Ellis JA, Brown CM, Barger B, Carlson NS. Influence of maternal obesity on labor induction: a systematic review and meta-analysis. J Mid wifery Womens Health. 2019;64(1):55–67. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 97.Dammer U, Bogner R, Weiss C, et al. Influence of body mass index on induction of labor: a historical cohort study. J Obstet Gynaecol Res. 2018;44(4):697–707. [DOI] [PubMed] [Google Scholar]
  • 98.Suidan RS, Rondon KC, Apuzzio JJ, Williams SF. Labor outcomes of obese clients undergoing induction of labor with misoprostol compared to dinoprostone. Am J Perinatol. 2015;30(2):187–192. [DOI] [PubMed] [Google Scholar]
  • 99.Hiersch L, Rosen H, Salzer L, Aviram A, Ben-Haroush A, Yogev Y. Does artificial rupturing of membranes in the active phase of labor enhance myometrial electrical activity?J Matern Fetal Neonatal Med. 2015;28(5):515–518. [DOI] [PubMed] [Google Scholar]
  • 100.Final report on the safety assessment of ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, glyceryl ricinoleate SE, ricinoleic acid, potassium ricinoleate, sodium ricinoleate, zinc ricinoleate, cetyl ricinoleate, ethyl ricinoleate, glycol ricinoleate, isopropyl ricinoleate, methyl ricinoleate, and octyldodecyl ricinoleate. Int J Toxicol. 2007;26Suppl 3:31–77. [DOI] [PubMed] [Google Scholar]
  • 101.Gilad R, Hochner H, Savitsky B, Porat S, Hochner-Celnikier D. Castor oil for induction of labor in post-date pregnancies: a randomized controlled trial. Women Birth. 2018;31(1):e26–e31. [DOI] [PubMed] [Google Scholar]
  • 102.Muñoz Balbontín Y, Stewart D, Shetty A, Fitton CA, McLay JS. Herbal medicinal product use during pregnancy and the postnatal period: a systematic review. Obstet Gynecol. 2019;133(5):920–932. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 103.Zamawe C, King C, Jennings HM, Mandiwa C, Fottrell E. Effectiveness and safety of herbal medicines for induction of labour: a systematic review and meta-analysis. BMJ Open. 2018;8(10):e022499. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 104.Smith CA, Armour M, Dahlen HG. Acupuncture or acupressure for induction of labour. Cochrane Database Syst Rev. 2017;10(10):CD002962. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 105.Rydahl E, Eriksen L, Juhl M. Effects of induction of labor prior to post-term in low-risk pregnancies: a systematic review. JBI Database System Rev Implement Rep. 2019;17(2):170–208. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 106.Middleton P, Shepherd E, Flenady V, McBain RD, Crowther CA. Planned early birth versus expectant management (waiting) for prelabour rupture of membranes at term (37 weeks or more). Cochrane Database Syst Rev. 2017;1(1):CD005302. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 107.Kjos SL, Henry OA, Montoro M, Buchanan TA, Mestman JH. Insulin-requiring diabetes in pregnancy: a randomized trial of active induction of labor and expectant management. Am J Obstet Gynecol. 1993;169(3):611–615. [DOI] [PubMed] [Google Scholar]
  • 108.Schunemann H, Brożzek J, Guyatt G, Oxman A. GRADE Handbook; 2013.https://gdt.gradepro.org/app/handbook/handbook.html

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