Perinatal Case Studies - Quality Improvement - Labor Induction Resources

The goal of induction of labor is to achieve vaginal delivery by stimulating uterine contractions before the spontaneous onset of labor. According to the National Center for Health Statistics, the overall rate of induction of labor in the United States has increased from 90 per 1,000 births in 1989 to 184 per 1,000 live births in 1997. Generally, induction of labor has merit as a therapeutic option when the benefits of expeditious delivery outweigh the risks of continuing the pregnancy. The benefits of labor induction must be weighed against the potential maternal or fetal risks associated with this procedure. The purpose of this bulletin is to review current methods for cervical ripening and induction of labor and to summarize the effectiveness of these approaches based on appropriately conducted outcomes-based research. These practice guidelines classify the indications for and contraindications to induction of labor, describe the various agents used for cervical ripening, cite methods used to induce labor and outline the requirements for the safe clinical use of the various methods of inducing labor.

More than 22% of all gravid women undergo induction of labor in the United States, and the overall rate of induction of labor in the US has more than doubled since 1990 to 225 per 1,000 live births in 2006 (1). The goal of induction of labor is to achieve vaginal delivery by stimulating uterine contractions before the spontaneous onset of labor. Generally, induction of labor has merit as a therapeutic option when the benefits of expeditious delivery outweigh the risks of continuing the pregnancy. The benefits of labor induction must be weighed against the potential maternal and fetal risks associated with this procedure (2). The purpose of this document is to review current methods for cervical ripening and induction of labor and to summarize the effectiveness of these approaches based on appropriately conducted outcomes-based research. These practice guidelines classify the indications for and contraindications to induction of labor, describe the various agents used for cervical ripening, cite methods used to induce labor and outline the requirements for the safe clinical use of the various methods of inducing labor.

The increasing trend of delivering at earlier gestational ages has raised concerns of the impact on maternal and infant health. The delicate balance of the risks and benefits associated with continuing a pregnancy versus delivering early remains challenging. Among singleton live births in the United States, the proportion of preterm births increased from 9.7% to 10.7% between 1996 and 2004. The increase in singleton preterm births occurred primarily among those delivered by cesarean section, with the largest percentage increase in late preterm births. For all maternal racial/ethnic groups, singleton cesarean section rates increased for each gestational age group. Singleton cesarean section rates for non-Hispanic black women increased at a faster pace among all preterm gestational age groups compared with non-Hispanic white and Hispanic women. Further research is needed to understand the underlying reasons for the increase in cesarean section deliveries resulting in preterm birth

OBJECTIVE: To quantify adverse neonatal and maternal outcomes associated with elective term delivery at less than 39 completed weeks of gestation.
STUDY DESIGN: Prospective observational study conducted in 27 hospitals over the course of 3 months in 2007.
RESULTS: Of 17,794 deliveries, 14,955 (84%) occurred at 37 weeks or greater. Of term deliveries, 6562 (44%) were planned, rather than spontaneous. Among the planned deliveries, 4645 (71%) were purely elective; 17.8% of infants delivered electively without medical indication at 37-38 weeks and 8% of those delivered electively at 38-39 weeks required admission to a newborn special care unit for an average of 4.5 days, compared with 4.6% of infants delivered at 39 weeks or beyond (P ! .001). Cesarean delivery rate in women undergoing induction of labor was not influenced by gestational age but was highly influenced by initial cervical dilatation and parity, ranging from 0% for parous women induced at 5 cm or greater to 50% for nulliparous women at 0 cm.
CONCLUSION: Elective delivery before 39 weeks’ gestation is associated with significant neonatal morbidity. Initial cervical dilatation is highly correlated with cesarean delivery among women undergoing induction of labor in both nulliparous and parous women. Elective delivery before 39 completed weeks’ gestation is inappropriate. Women contemplating elective induction at or beyond 39 weeks’ gestation with an unfavorable cervix should be counseled regarding an increased rate of cesarean delivery.

Induction of labor has become routine practice in perinatal units across the United States, with rates reaching a high of 21.2% of births in 2003-2004. This article describes the process our institution used to standardize the criteria for scheduling inductions. Specifically, we aimed to increase the consistency in practice for scheduling and performing elective inductions, including mandating gestational age of 39 completed weeks, ensuring cervical ripeness, and disallowing the use of cervical ripening agents. The nurses’ participation, from planning to implementation, was critical in the success of this evidence-based practice change.

OBJECTIVE: To examine the effects that medical staff education and a new process for scheduling inductions had on decreasing inappropriate inductions.
METHODS: At our institution in 2004, guidelines were developed and shared with the medical staff and reinforced in 2005. The guidelines for elective induction required patients to have completed 39 weeks of gestation and to have a Bishop score of at least 8 for nulliparas and 6 for multiparas. In 2006, the induction scheduling process was changed and the guidelines were strictly enforced. All scheduled inductions during the same 3-month time period (June through August) in 2004 (n=533) and 2005 (n=454) and during a 13-month period from November 2006 to December 2007 (n=1,806) were compared. Outcomes included elective inductions less than 39 weeks, cesarean birth rate for elective inductions among nulliparas, and the overall induction rate.
RESULTS: From 2004-2007, the overall induction rate dropped from 24.9% to 16.6%, a 33% reduction(P<.001); the elective induction rate dropped from 9.1% to 6.4%, a 30% reduction (P<.001); the percentage of elective inductions before 39 weeks of gestation dropped from 11.8% to 4.3%, a decrease of 64% (P<.001); and the frequency of cesarean delivery among nulliparas undergoing elective induction dropped from 34.5% to 13.8%, a decrease of 60%. (P=.01).
CONCLUSION: Medical staff education and the development and enforcement of induction guidelines contributed to a decrease in inappropriate inductions, a lower cesarean birth rate for electively induced nulliparas, and a lower elective and overall induction rate.

OBJECTIVES: To estimate women’s understanding of the definition of full term and the gestational age at which it is safe to deliver an otherwise healthy pregnancy. METHODS: A national sample of 650 insured women who recently gave birth were surveyed about their beliefs related to the meaning of full term and the safety of delivery at various gestational ages. Descriptive statistics including means and 95% confidence intervals were calculated for the demographic variables and survey measures; multivariate logistic regression analyses were also performed. RESULTS: Twenty-four percent of women surveyed considered a baby of 34–36 weeks of gestation to be full term, and 50.8% believed full term to occur at 37–38 weeks of gestation, while only 25.2% considered full term to occur at 39–40 weeks of gestation. In response to,“What is the earliest point in pregnancy that it is safe to deliver the baby, should there be no other medical complications requiring early delivery?” 51.7% choose 34–36 weeks of gestation, and 40.7% choose 37–38 weeks of gestation, while only 7.6% choose 39–40 weeks of gestation. CONCLUSION: The American College of Obstetricians and Gynecologists recommends that elective deliveries not occur before 39 weeks of gestation. However, many women believe that full term is reached before 37 weeks of gestation, and most believe full term occurs before 39 weeks of gestation. Nearly half believe it is safe to deliver before 37 weeks of gestation, and almost all believe it is safe to deliver before 39 weeks of gestation. The data reported here suggest that many women believe that term is reached early and that a safe delivery does not require waiting to 39 weeks of gestation.

One of the biggest challenges a newborn faces after birth is the task of making a smooth transition to air breathing. This task is complicated by the fact that fetal lungs are full of fluid which must be cleared rapidly to allow for gas exchange. Respiratory morbidity as a result of failure to clear fetal lung fluid is not uncommon, and can be particularly problematic in some infants delivered by elective cesarean delivery (ECS). Given the high rates of cesarean deliveries in the USA and worldwide, the public health and economic impact of morbidity in this subgroup is considerable. Whereas the occurrence of birth asphyxia, trauma, and meconium aspiration is reduced by elective Cesarean delivery, the risk of respiratory distress secondary to transient tachypnea of the newborn,surfactant deficiency, and pulmonary hypertension is increased. It is clear that physiologic events in the last few weeks of pregnancy coupled with the onset of spontaneous labor are accompanied by changes in the hormonal milieu of the fetus and its mother, resulting in preparation of the fetus for neonatal transition. Rapid clearance of fetal lung fluid is a key part of these changes, and is mediated in large part by transepithelial Na reabsorption through amiloride-sensitive Na channels in the alveolar epithelial cells, with only a limited contribution from mechanical factors and Starling forces. This chapter discusses the physiologic mechanisms underlying fetal lung fluid absorption and explores potential strategies for facilitating neonatal transition when infants are delivered by ECS before the onset of spontaneous labor.

Objective: To determine the effects of elective induction on the risk of cesarean delivery in a cohort of women with low-risk term pregnancies and to evaluate the costs of elective induction services within our hospital system. Methods: Records of 1135 eligible women with low-risk, singleton, vertex pregnancies at 38 – 41 weeks’ gestation who were eligible for vaginal delivery were analyzed retrospectively after elective induction (n 􏰆􏰆􏰆 263) or spontaneous labor (n 􏰆􏰆􏰆 872). Outcome measures included cesarean delivery and direct costs. Variables evaluated were parity, maternal age, estimated gestational age, birth weight, prior cesarean delivery, epidural anesthetic use, and provider category. Analysis was by univariable and multivariable regression modeling. Results: Elective induction placed nulliparas at a twofold higher risk for cesarean delivery (odds ratio 2.4, 95% confidence interval 1.2, 4.9) after adjustment for birth weight, maternal age, and gestational age. We found a significantly increased risk of cesarean delivery with increased birth weight for nulliparas (2– 66.7%). Increasing maternal age increased the risk of cesarean delivery in all parity groups (P <<< .05), but particularly among nulliparas (3–26.3%) (P <<< .001). Electively induced labors that ended in vaginal delivery cost $273 more and required an average of 4 hours more in the hospital before delivery than did noninduced vaginal deliveries (P <<< .001). Conclusion: Elective induction significantly increased the risk of cesarean delivery for nulliparas, and increased in-hospital predelivery time and costs. (Obstet Gynecol 2000; 95:917–22. © 2000 by The American College of Obstetri- cians and Gynecologists.)

OBJECTIVE: To establish whether the timing of delivery between 37 and 42 weeks gestation influences neonatal respiratory outcome and thus provide information which can be used to aid planning of elective delivery at term.
DESIGN: All cases of respiratory distress syndrome or transient tachypnoea at term requiring admission to the neonatal intensive care unit were recorded prospectively for nine years.
SETTING: Rosie Maternity Hospital, Cambridge.
SUBJECTS: During this time 33,289 deliveries occurred at or after 37 weeks of gestation.
MEASURES: This information enabled calculation of the relative risk of respiratory morbidity for respiratory distress syndrome or transient tachypnoea in relation to mode of delivery and onset of parturition for each week of gestation at term.
RESULTS: The incidence of respiratory distress syndrome at term was 2.2/ 1000 deliveries (95 % CI; 1.7-2.7). The incidence of transient tachypnoea was 5.7/1000 deliveries (95 % CI; 4.9-65). The incidence of respiratory morbidity was significantly higher for the group delivered by caesarean section before the onset of labour (35.5/ 1000) compared with caesarean section during labour (12.2/1000) (odds ratio, 2.9; 95% CI 1.9-4.4; P <0.001), and compared with vaginal delivery (5.3/1000) (odds ratio, 6.8; 95 % CI 52-8.9; P < 0.001). The relative risk of neonatal respiratory morbidity for delivery by caesarean section before the onset of labour during the week 37+0 to 37+6 compared with the week 38+0 to 38+6 was 1.74 (95 % CI 1.1 -2.8 ; P < 0.02) and during the week 38+O to 38+6 compared with the week 39+0 to 39+6 was 2.4 (95% CI 1.2-4.8; P < 0.02).
CONCLUSIONS: A significant reduction in neonatal respiratory morbidity would be obtained if elective caesarean section was performed in the week 39+0 to 39+6 of pregnancy.

OBJECTIVE: The American College of Obstetricians and Gynecologists has recommended that elective deliveries not be performed before 39 weeks of gestation, to minimize prematurity-related neonatal complications. Because a worrisome number of elective deliveries were occurring before 39 weeks of gestation in our system, we developed and implemented a program to decrease the number of these early term elective deliveries. Secondary objectives were to monitor relevant clinical outcomes.
METHODS: The electronic medical records of an integrated health care system involving nine labor and delivery units in Utah were queried to establish the incidence of patients admitted for elective induction of labor or planned elective cesarean delivery. These facilities have open staff models with obstetricians, family practitioners, and certified nurse midwives. Guidelines were developed and implemented to discourage early term elective deliveries. The prevalence of early term elective deliveries was tracked and reported back regularly to the obstetric leadership and obstetric departments at each facility.
RESULTS: The baseline prevalence of early term elective deliveries was 28% of all elective deliveries before the initiation of the program. Within 6 months of initiating the program, the incidence of near-term elective deliveries decreased to less than 10% and after 6 years continues to be less than 3%. A reduced length of stay in labor and delivery occurred with the introduction of the program, and there were no adverse effects on secondary clinical outcomes.
CONCLUSION: With institutional commitment, it is possible to substantially reduce and sustain a decline in the incidence of elective deliveries before 39 weeks of gestation.

OBJECTIVE: Our goal was to lower unplanned primary cesarean deliveries by reducing elective inductions. STUDY DESIGN: To implement and sustain an induction management program, a committee of care providers reviewed induction rates. “Elective” and other categories were defined. An induction consent form was drafted. Consent compliance, induction rates, hours in labor and delivery and mode of delivery were evaluated. Outcomes were compared with historical data from 2 years earlier. RESULTS: A total of 10,166 nulliparas and 9869 multiparas attempted vaginal deliveries. Elective inductions decreased significantly, from 4.3% to 0.8% in nulliparas and from 13% to 9.5% in multiparas. A longer time to delivery was seen for both nulliparas (5.2 hours) and multiparas (4 hours) with elective inductions. Unplanned primary cesarean delivery rates are significantly lower in spontaneously laboring women, compared with those induced. CONCLUSION: A program aimed at reducing elective inductions was successfully implemented and sustained.

Aims. 1. Ascertain antenatal and intrapartum risk factors for term neonates ventilated primarily for ‘perinatal asphyxia’. 2. Describe the neonatal morbidity and mortality. Methods. Population-based case control cohort study. Setting. Sydney and four large rural/urban health areas in New South Wales. Subjects. Singleton term infants, no major congenital anomaly: subset of 83 infants ventilated primarily for ‘asphyxia’ from 182 cases admitted to a tertiary neonatal intensive care unit (NICU) for mechanical ventilation, 550 randomly selected controls. Outcome. Risk factors for case status by maternal, antenatal, labor, delivery, and combined epochs, adjusted odds ratios (OR), 95 per cent confidence intervals (CI), p􏰁0.05. Results. Predictors of case status by multivariate epochs: Primigravida (1.8 [1.1, 2.8]), thyroid disease (7.8 [1.1, 57.0]), any antenatal complication (5.1 [3.0, 8.6]), growth restriction (4.2 [1.7, 10.4]), male gender (2.1 [1.3, 3.5]), gestational age 􏰂40 weeks (1.9 (1.1, 3.3)), prolonged rupture of membranes (9.7 [1.3, 72.5]), complicated labor (6.6 [3.7, 11.9]), induced labor (2.2 [1.3, 3.9]), prostaglandins 2.46 [1.23, 4.91]), maternal pyrexia (10.8 [2.8, 42.7]), placental hemorrhage in labor (OR 4.24 [1.45, 12.42]), forceps delivery (4.1 [1.9, 8.5]), emergency cesarean section (4.7 [2.6, 8.7]). Twenty case infants (24%) and no control infants died. Conclusions. This study has shown maternal and antepartum risk factors for severe neonatal morbidity in term infants. More centers need to become interested in the term baby, so that a larger multicenter study can further elucidate the heterogeneous causal pathways to term neonatal morbidity.

AIMS: 1. Ascertain antenatal and intrapartum risk factors for term neonates ventilated primarily for respiratory problems. 2. Describe the neonatal morbidity and mortality. Methods. Population-based case control cohort study. SETTING: Sydney and four large rural/urban Health Areas in New South Wales, 1996. SUBJECTS: Singleton term infants, no major congenital anomaly: subset of 99 infants ventilated primarily for respiratory problems from 182 cases admitted to a tertiary neonatal intensive care unit (NICU) for mechanical ventilation, and 550 randomly selected controls. OUTCOME: Risk factors for case status by maternal, antenatal, labor, delivery, and combined epochs, adjusted Odds Ratios (OR), 95 per cent Confidence Intervals (CI), p<0.05. RESULTS: Predictors of case status by multivariate epochs: mother’s age >35 years (1.9 (1.1, 3.2) p<0.03), primigravida (1.8 (1.1, 2.8) p<0.01), any antenatal complication (3.8 (2.4, 5.9) p<0.0001), birth weigh<3rd percentile (3.7 (1.5, 9.1) p<0.006), gestational diabetes (2.9 (1.3, 6.9) p<0.01), maternal pyrexia (6.5 (1.6, 27.2) p<0.01), birth weight >90th percentile (1.8 (1.01, 3.2) p<0.047), gestation 37–38 weeks (2.3 (1.5, 3.6) p<0.0004), forceps (4.4 (2.1, 9.1) p<0.0001), elective cesarean section (3.7 (2.0, 6.5) p<0.0001), emergency cesarean section (4.5 (2.4, 8.4) p<0.0001). Case mortality rate was 5 per cent. CONCLUSIONS: The pathways to neonatal respiratory morbidity in term infants are multifactorial. Several areas which warrant more in-depth study are: elective cesarean section at 37–38 weeks gestation, fetal growth restriction, macrosomia and the pattern of in-utero growth, maternal weight gain during pregnancy, gestational diabetes, pyrexia in labor and the role of chorioamnionitis.

Background: Because of increased rates of respiratory complications, elective cesarean delivery is discouraged before 39 weeks of gestation unless there is evidence of fetal lung maturity. We assessed associations between elective cesarean delivery at term (37 weeks of gestation or longer) but before 39 weeks of gestation and neonatal outcomes. Methods: We studied a cohort of consecutive patients undergoing repeat cesarean sections performed at 19 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal–Fetal Medicine Units Network from 1999 through 2002. Women with viable singleton pregnancies delivered electively (i.e., before the onset of labor and without any recognized indications for delivery before 39 weeks of gestation) were included. The primary outcome was the composite of neonatal death and any of several adverse events, including respiratory complications, treated hypoglycemia, newborn sepsis, and admission to the neonatal intensive care unit (ICU). Results:Of 24,077 repeat cesarean deliveries at term, 13,258 were performed electively; of these, 35.8% were performed before 39 completed weeks of gestation (6.3% at 37 weeks and 29.5% at 38 weeks) and 49.1% at 39 weeks of gestation. One neonatal death occurred. As compared with births at 39 weeks, births at 37 weeks and at 38 weeks were associated with an increased risk of the primary outcome (adjusted odds ratio for births at 37 weeks, 2.1; 95% confidence interval [CI], 1.7 to 2.5; adjusted odds ratio for births at 38 weeks, 1.5; 95% CI, 1.3 to 1.7; P for trend <0.001). The rates of adverse respiratory outcomes, mechanical ventilation, newborn sepsis, hypoglycemia, admission to the neonatal ICU, and hospitalization for 5 days or more were increased by a factor of 1.8 to 4.2 for births at 37 weeks and 1.3 to 2.1 for births at 38 weeks. Conclusions: Elective repeat cesarean delivery before 39 weeks of gestation is common and is associated with respiratory and other adverse neonatal outcomes.