Rate Of Labor Induction Research Articles

Indications for induction of labour: a best‐evidence review

Rates of labour induction are increasing. To review the evidence supporting indications for induction. We listed indications for labour induction and then reviewed the evidence. We searched MEDLINE and the Cochrane Library between 1980 and April 2008 using several terms and combinations, including induction of labour, premature rupture of membranes, post-term pregnancy, preterm prelabour rupture of membranes (PROM), multiple gestation, suspected macrosomia, diabetes, gestational diabetes mellitus, cardiac disease, fetal anomalies, systemic lupus erythematosis, oligohydramnios, alloimmunization, rhesus disease, intrahepatic cholestasis of pregnancy (IHCP), and intrauterine growth restriction (IUGR). We performed a review of the literature supporting each indication. We identified 1387 abstracts and reviewed 418 full text articles. We preferentially included high-quality systematic reviews or large randomised trials. Where no such studies existed, we included the best evidence available from smaller randomised trials and observational studies. We included 34 full text articles. For each indication, we assigned levels of evidence and grades of recommendation based upon the GRADE system. Recommendations for induction of labour for post-term gestation, PROM at term, and premature rupture of membranes near term with pulmonary maturity are supported by the evidence. Induction for IUGR before term reduces intrauterine fetal death, but increases caesarean deliveries and neonatal deaths. Evidence is insufficient to support induction for women with insulin-requiring diabetes, twin gestation, fetal macrosomia, oligohydramnios, cholestasis of pregnancy, maternal cardiac disease and fetal gastroschisis. Research is needed to determine risks and benefits of induction for many commonly advocated clinical indications.

The active management of risk in multiparous pregnancy at term: association between a higher preventive labor induction rate and improved birth outcomes

To determine whether exposure of multiparous women to a high rate of preventive labor induction was associated with a significantly lower cesarean delivery rate. Retrospective cohort study involving 123 multiparous women, who were exposed to the frequent use of preventive labor induction, and 304 multiparous women, who received standard management. Rates of cesarean delivery and other adverse birth outcomes were compared in the 2 groups. Logistic regression controlled for confounding covariates. The exposed group had a lower cesarean delivery rate (adjusted odds ratio, 0.09; 0.8% vs 9.9%; P = .02) and a higher uncomplicated vaginal delivery rate (odds ratio, 0.53; 78.9% vs 66.4%; P = .01). Exposure was not associated with higher rates of other adverse birth outcomes. Exposure of multiparous women to a high rate of preventive labor induction was significantly associated with improved birth outcomes, including a very low cesarean delivery rate. A prospective randomized trial is needed to determine causality.

Active management of risk in nulliparous pregnancy at term: association between a higher preventive labor induction rate and improved birth outcomes

The objective of the study was to determine whether exposure of nulliparous women to a high rate of preventive labor induction was associated with improvement in birth health. A risk-scoring system was used to guide the frequent use of preventive labor induction in 100 nulliparous women. The birth outcomes of this group were compared with those of 352 nulliparous women who received usual care. Cesarean delivery was the primary study outcome. The Adverse Outcome Index and the rate of uncomplicated vaginal delivery were used to measure overall birth health. The exposed group experienced a higher labor induction rate (48% vs 23.6%; P < .001), a lower cesarean rate (9% vs 25.8%; adjusted odds ratio, 0.36; P = .02), and better composite birth outcomes. Exposure of nulliparous women to a high preventive induction rate was significantly associated with improvement in birth health. Prospective randomized trials are needed to further explore the utility of risk-guided preventive labor induction.

Vaginismus as an independent risk factor for cesarean delivery

Objective. The present study was aimed to investigate pregnancy outcome of patients with vaginismus, and specifically the relationship between vaginismus and cesarean delivery.Methods. A population based study comparing all pregnancies in patients with and without vaginismus was conducted. Patients lacking prenatal care were excluded from the analysis. Deliveries occurred during the years 1988–2007. A multivariate logistic regression model, with backward elimination, was constructed to find independent risk factors associated with vaginismus.Results. During the study period there were 192,954 deliveries, of which 118 occurred in patients with vaginismus. Patients with vaginismus tended to be younger (26.04±4.89 vs. 28.61±5.83; p < 0.001) and delivered smaller children (3024.2±517 g vs. 3160.9±576 g; p = 0.01) when compared with patients without vaginismus. Patients with vaginismus had higher rates of infertility treatments (5.9%vs. 2.7%, odds ratio [OR] 2.3; 95% confidence interval [CI] 1.1–4.9; p = 0.04) and labor induction (37.3%vs. 27.4%, OR 1.6; 95% CI 1.1–2.3; p = 0.02), vacuum extraction (9.3%vs. 2.8%, OR 3.6, 95% CI 1.9–6.7; p < 0.001), and cesarean delivery (39.0%vs. 14.5%, OR 3.8; 95% CI 2.6–5.5; p < 0.001) when compared with the comparison group. Even after controlling for possible confounders associated with cesarean delivery such as previous cesarean delivery, pathological presentations, and fetal distress, vaginismus remained as an independent risk factor for cesarean delivery (OR 7.1; 95% CI 4.5–11.1; p < 0.001).Conclusion. Vaginismus is an independent risk factor for cesarean delivery.

Rising rates of obstetric interventions: exploring the determinants of induction of labour

Rising rates of obstetric interventions in the UK are a concern for health-care providers and the public. Our aims were to identify the socio-demographic and clinical factors (case mix) predictive of one of the most common obstetric interventions, induction of labour (IOL), and quantify the extent to which observed rates can be explained by case mix factors. We conducted a comparative analysis of induced and spontaneous labours, using contemporary clinical data from the Aberdeen Maternity and Neonatal Databank. Cases complicated by antenatal intrauterine death or a previous or planned caesarean section were excluded. In total, 17,736 cases were included in the analysis. In 5727 (32.3%) cases labour was induced and in 12,009 (67.7%) cases it was spontaneous. Multivariate logistic regression modelling was used. In total, 18 case mix factors were predictive of IOL. Among these were well-recognized clinical indications for IOL such as pre-labour rupture of membranes (OR 3.29, 95% CI 2.90, 3.73) and prolonged pregnancy (OR 4.15, 95% CI 3.82, 4.50) and previously unreported case mix factors (residing an intermediate distance and travel time from hospital) (OR 1.27, 95% CI 1.18, 1.37; BMI >35 OR 1.37, 95% CI 1.14, 1.65). Case mix explained 71.5% of the observed rate of IOL. More than one-quarter of the rate of IOL remains unexplained by case mix factors. This may be explained by women's preferences for care and clinicians' practice.

Sectio-Häufigkeit nach Sterilitätsbehandlung bei Einlingen: Eine Auswertung der Hessischen Perinatalerhebung (HEPE)

This study investigates which factors increase the probability of the need to perform a Caesarean section in an uncomplicated single-foetus pregnancy following infertility treatment. The Hessian Perinatal Registry (HEPE) was used as a basis to determine the development of the rate of Caesarean sections and the delivery method for births in 2007. It is linked to anamnestic and perinatal risks and the foetal and maternal outcome. The total rate of Caesarean sections in the state of Hesse has doubled in a period of over 15 years and stood at 33.0 % in 2007. The same period also saw a rise in the percentage of births that followed infertility treatment, for which an increased risk for multiple-foetus pregnancies can be verified. A comparison of mature single-foetuses in cephalic presentation (at 37-41 weeks gestation) with and without preceding infertility treatment shows the risk involved for Caesarean section to have increased (caesarean section rate 24.7 vs. 31.2 %). The higher rate of Caesarean sections following infertility treatment is associated with higher pregnancy risks (family history, allergies, obesity, premature contractions) and can lead to a higher rate of labour induction, but remains an independent risk even after these factors have been controlled (OR = 1.74, 95 % CI = 1.68-1.79). The risks for Caesarean section are increased even for uncomplicated pregnancies when they follow infertility treatment. It can be assumed that, amongst other things, increased safety needs for couples and doctors together with more high-tech intensive care of pregnancies following infertility treatment will be required. In the event of a planned Caesarean section, comprehensive explanation of the risks involved will be necessary.

Comparative efficacy and safety of vaginal misoprostol versus dinoprostone vaginal insert in labor induction at term: a randomized trial

To compare efficacy and safety of vaginal misoprostol (PGE(1) analog) with dinoprostone (PGE(2) analog) vaginal insert for labor induction in term pregnancies. A total of 112 women with singleton pregnancies of > or =37 weeks of gestation, and low Bishop scores underwent labor induction. The subjects were randomized to receive either 50 mug misoprostol intravaginally every 4 h to a maximum of five doses or a 10 mg dinoprostone vaginal insert for a maximum of 12 h. Time interval from induction to vaginal delivery, vaginal delivery rates within 12 and 24 h, requirement of oxytocin augmentation, incidence of tachysystole and uterine hyperstimulation, mode of delivery, rate of cesarean section due to fetal distress and neonatal outcome were outcome measures. Student's t test, Chi square test, Fischer's exact test were used for statistical analysis. Time interval from induction to vaginal delivery was found to be significantly shorter in misoprostol group when compared to dinoprostone subjects (680 +/- 329 min vs. 1070 +/- 435 min, P < 0.001). Vaginal delivery rates within 12 h were found to be significantly higher with misoprostol induction [n = 37 (66%) vs. n = 25 (44.6%); P = 0.02], whereas vaginal delivery rates in 24 h did not differ significantly between groups [n = 41 (73.2%) vs. n = 36 (64.2%); P = 0.3]. More subjects required oxytocin augmentation in dinoprostone group [n = 35 (62.5%) vs. n = 20 (35.7%), P = 0.005] and cardiotocography tracings revealed early decelerations occurring more frequently with misoprostol induction (10.7 vs. 0%, P = 0.03). Tachysystole and uterine hyperstimulation, mode of delivery, rate of cesarean sections due to fetal distress and adverse neonatal outcome were not demonstrated to be significantly different between groups (P = 1, P = 0.5, P = 0.4, P = 0.22, P = 0.5). Using vaginal misoprostol is an effective way of labor induction in term pregnant women with unfavorable cervices, since it is associated with a shorter duration of labor induction and higher rates of vaginal delivery within 12 h. Misoprostol and dinoprostone are equally safe, since misoprostol did not result in a rise in maternal and neonatal morbidity, namely, tachysystole, uterine hyperstimulation, cesarean section rates and admission to neonatal intensive care units as reported previously in literature.

Racial Disparities in Term Induction of Labor Rates in Illinois

To determine whether the increase in the rate of labor induction at term is significantly different among women of different races. Data from the National Center for Health Statistics were used to identify pregnant women with singletons at 37-41 weeks gestation from 1991 to 2003 in Illinois. The independent association between the induction rate at term and maternal race was evaluated using longitudinal regression. Covariates considered were maternal demographic and obstetrical characteristics; those that changed the estimated association between race and induction of labor by at least 20% were included in the final model. The mean annual induction rates rose significantly during the study period both for the entire population and for each racial group. After adjusting for maternal demographic characteristics, obstetrical risk factors for medically-indicated induction, and for county-level malpractice premium charges, each 1% increase in the proportion of the white and non-white/non-African American populations within a county was associated with significantly higher induction rates (74% and 92%, respectively) in the county. Although induction rates have increased for all women, the rate of rise has increased disproportionately among women of non-African American race.

Introducing caesarean section audit in a regional teaching hospital in The Netherlands

Objective The increase in caesarean section rates is considered a reason for serious public health concern. With the objective to create awareness and initiate local discussion, obstetric audit was introduced in a regional teaching hospital in The Netherlands. Study design Caesarean section audit was introduced during the existing daily reports meetings from August 1, 2005 to June 1, 2006 in The Haga hospital, a large teaching hospital in The Hague, The Netherlands. All caesarean sections were discussed with regard to indication, classification and audited for ‘lack of necessity’. For comparing intervention rates with the period prior to audit, Chi-square test with Yates correction for 2 × 2 tables was used. Results Of 1221 deliveries, 228 were caesarean sections (18.7%) while prior to the audit period there were 1216 deliveries with 284 were caesarean sections (23.4%). The caesarean section rate is significantly lower during the audit period. Assisted vaginal deliveries, neonatal outcome, and induction of labor rates were comparable. Concerning the audit question ‘could caesarean section have been prevented’, there was discussion in 24.4% of cases. In 6.7% of caesarean sections, consensus about lack of necessity was achieved. Conclusion Introducing caesarean section audit during the existing structure of daily report meetings in a regional teaching hospital is both feasible and practical. It creates awareness and encourages discussion among staff members concerning indications for caesarean sections and lack of necessity. Furthermore, there was a significant decrease in caesarean section rate during the audit period.

344: Preeclampsia is a risk factor for cesarean delivery in the setting of induction of labor

INDUCTION OF LABOR LENA KIM, ANJALI KAIMAL, YVONNE CHENG, SHANI DELANEY, ANGIE CHILD, AARON CAUGHEY, Kaiser Permanente, Obstetrics and Gynecology, Hayward, California, University of California, San Francisco, San Francisco, California OBJECTIVE: To determine if women with preeclampsia have a higher risk of labor induction failure than women without preeclampsia. STUDY DESIGN: We conducted a retrospective cohort study to examine cesarean delivery rates between women with and without preeclampsia undergoing labor induction in four subgroups: term nulliparous, term multiparous, preterm nulliparous, and preterm multiparous. We included all induced singleton pregnancies 24 weeks gestational age at a single institution. Multivariable logistic regression analysis was used to control for parity and gestational age, as well as other potential confounders (maternal age, race/ethnicity, prior cesarean history, epidural use, medical comorbidities, and BMI). RESULTS: Our cohort included 3,481 women. Term nulliparous preeclamptics had higher cesarean delivery rates than non-preeclamptics (n 1761, 33 v. 24%, p 0.003). Although not significant, term multiparous preeclamptics had more cesarean deliveries as well (n 1213, 17 v. 13%, p 0.305). Preterm preeclamptics also had significantly higher labor induction failure rates compared to non-preeclamptics among both nulliparous (n 254, 26 v. 7%, p 0.001) and multiparous (n 253, 26 v. 8%, p 0.001) women. In multivariable analysis preeclampsia still conferred an increased risk of labor induction failure (OR 1.88, 95% CI 1.38 2.56). CONCLUSION: Women with preeclampsia had higher failure rates of labor induction than women without preeclampsia regardless of parity or gestational age at delivery, even when controlling for other potential confounders.

Elective Induction of Labor

Induction of labor rates have more than doubled nationwide in the past 15 years. The increase in medically induced inductions was slower than the overall increase, suggesting that inductions for marginal or elective reasons rose more rapidly. Elective inductions seem to account for at least half of all inductions and 10% of all deliveries. Whether the experience of an elective induction is satisfactory to the patient, obstetrician, and intrapartum crew warrants more widespread attention. Cesarean rates are high for nulliparas undergoing an induction with an unfavorable cervix. Prospective studies are limited or nonexistent to recommend induction of labor for elective or marginal indications. Until more prospective work is performed, it will be difficult to evaluate the true impact of the elective induction of labor on population-wide cesarean delivery rates. Strategies for increased obstetrician awareness are proposed through practice guidelines and through clinical research trials.

A preventive approach to obstetric care in a rural hospital: association between higher rates of preventive labor induction and lower rates of cesarean delivery.

Annual cesarean delivery rates in North America are increasing. Despite the morbidity associated with cesarean delivery, a safe preventive strategy to reduce the use of this procedure has not been forthcoming. During the 1990s, clinicians in a rural hospital developed a method of care involving prostaglandin-assisted preventive labor induction. An inverse relationship was noted between yearly hospital rates of labor induction and cesarean delivery. The purpose of our study was to compare cesarean delivery rates between practitioners who often used preventive induction and practitioners who did not, while controlling for patient mix and differences in practice style. Between 1993 and 1997, different hospital practitioners used risk-guided prostaglandin-assisted preventive labor induction with differing intensity. We used a retrospective cohort design, based on the practitioner providing prenatal care, to compare birth outcomes in women exposed to this alternative method of care with those in women not exposed. Multiple logistic regression analysis controlled for patient characteristics and clustering by practitioner. The exposed group (n = 794), as compared with the nonexposed group (n = 1,075), had a higher labor induction rate (31.4% vs 20.4%, P <.001), a greater use of prostaglandin E2 (23.3% vs 15.7%, P <.001), and a lower cesarean delivery rate (5.3% vs 11.8%, P <.001). Adjustment for cluster effects, patient characteristics, and the use of epidural analgesia did not eliminate the significant association between exposure to this preventive method of care and a lower cesarean delivery rate. Rates of other adverse birth outcomes were either unchanged or reduced in the exposed group. A preventive approach to reducing cesarean deliveries may be possible. This study found that practitioners who often used risk-guided, prostaglandin-assisted labor induction had a lower cesarean delivery rate without increases in rates of other adverse birth outcomes. Randomized controlled trials of this method of care are warranted.

Conséquences obstétricales et néonatales du diabète gestationnel dans la population du sud de l'île de la Réunion

Objective To assess maternal and fetal outcomes in patients with gestational diabetes mellitus. Patients and methods A retrospective study was conducted at the Sud-Reunion Hospital's maternity (French overseas department located in the Indian Ocean), during the period from January 1, 2001, through December 31, 2004. During this period, 1172 pregnant women presenting gestational diabetes mellitus were compared with 1172 non-diabetic controls matched on the basis of age, parity. Student t test, Pearson chi-square test and logistic regression model were used for statistical analysis. Results Gestational diabetes mellitus complicates about 7.5% of pregnancies in Reunion Island. Its occurrence was associated with a significantly increased prevalence of pre-pregnancy obesity (27 versus 9.4%) and chronic hypertension (5.3 versus 3.3%). The prevalence of preeclampsia and obstetrical vascular disorders were not different between the two groups, respectively 2.2 versus 2.7% ( P = 0.43) and 6.2 versus 4.4% ( P = 0.06). The rate of caesarean sections and inductions of labour was increased in the study group. The term of delivery was inferior in the study group, consecutive to increased rate of labour induction at 38 week-gestation. Macrosomia and large for gestational age (LGA) newborns rate were significantly higher in the study group, respectively 8.9 versus 4.2% and 22.5 versus 10.1% ( P < 0.001) but the rate of admission into neonatal unit was not significantly different. Discussion and conclusion Active management of gestational diabetes mellitus is associated with low maternal and perinatal morbidity. While age and parity are controlled by the study design, the prevalence of preeclampsia and gestational hypertension are not increased in women presenting gestational diabetes mellitus.

Effect of maternal congenital heart defects on labor and delivery outcome: A population-based study

Objective. The primary objective of this study was to characterize the delivery outcome of parturients with congenital heart defects (CHD), from maternal and from neonatal perspectives.Study design. A retrospective population-based study was conducted, covering a 13-year period (1989–2002) with an aggregate of 151 487 deliveries of all women with and without CHD. Maternal demographics, obstetrical and medical history, delivery outcome, and neonatal outcome were drawn from a computerized perinatal database.Results. Sixty-seven women with CHD had 156 deliveries. The severity of CHD, based on the New York Heart Association (NYHA) classification, was I or II in 99.1% of the deliveries. CHD patients had significantly higher rates of labor induction and neonatal malformations. Maternal CHD was discovered as an independent risk factor associated with neonatal malformations (OR 2.10, 95% CI 1.18–3.72). No significant differences were noted between women with CHD and the controls regarding maternal morbidities and Apgar scores.Conclusions. The labor outcome of CHD patients with NYHA classification I and II resembles that of non-CHD women in a tertiary center setting. Neonates of CHD mothers have higher rates of congenital malformations even among asymptomatic or mildly symptomatic mothers. A careful sonographic follow-up is warranted among all pregnancies of CHD patients.

The active management of risk in multiparous women at term: An association between a higher preventive labor induction rate and a lower cesarean delivery rate

The active management of risk in multiparous women at term: An association between a higher preventive labor induction rate and a lower cesarean delivery rate

Preinduction Cervical Assessment

The rate of labor induction is increasing in the United States. Methods for quantifying cervical factors have been developed to identify patients who may benefit from cervical ripening before induction. The first cervical scoring systems used digital examination. More recently, cervical ultrasound and testing for the presence of fetal fibronectin have been suggested to evaluate cervical readiness for labor induction, but neither of these methods provides a significant improvement over digital examination. The Bishop score, the most widely used digital examination scoring system, still is the most cost effective and accurate method of evaluating the cervix before labor induction.

Elective Induction of Labor

Induction of labor rates have more than doubled nationwide in the past 15 years. The increase in medically induced inductions was slower than the overall increase, suggesting that inductions for marginal or elective reasons rose more rapidly. Elective inductions seem to account for at least half of all inductions and 10% of all deliveries. Whether the experience of an elective induction is satisfactory to the patient, obstetrician, and intrapartum crew warrants more widespread attention. Cesarean rates are high for nulliparas undergoing an induction with an unfavorable cervix. Prospective studies are limited or nonexistent to recommend induction of labor for elective or marginal indications. Until more prospective work is performed, it will be difficult to evaluate the true impact of the elective induction of labor on population-wide cesarean delivery rates. Strategies for increased obstetrician awareness are proposed through practice guidelines and through clinical research trials.

Trends in obstetric interventions in the Dutch obstetrical care system in the period 1993–2002

Objective To determine trends in induction of labour-, instrumental vaginal delivery- and caesarean section rates in the Netherlands in the period 1993–2002. Study design Data derived from The Netherlands Perinatal Registry and Statistics Netherlands were used to calculate annual rates for induction of labour, instrumental vaginal delivery and caesarean section. Regarding caesarean section, rates were also calculated for different subgroups with respect to parity, presentation of the fetus, gestational age and multiple pregnancies. In the subgroup of women with a singleton fetus in vertex presentation between 37 and 42 weeks of gestation instrumental delivery rates were compared for women with induced labours and women in spontaneous labour. Results The overall CS rate rose from 8.1 to 13.6%. Proportionally the rise was greatest for breech presentation (+37.7%), multiple gestations (+12.7%) and women delivering between 24 and 28 weeks (+9.5%). However, in absolute numbers the rise was most impressive in the group of women with a singleton fetus in vertex presentation between 37 and 42 weeks of gestation. Rate of induction of labour and instrumental vaginal delivery remained constant (approximately 15% respectively 10% of all deliveries). In nulliparous term women with singletons in vertex presentation the CS rate increased with 8.0% to a rate of 20.7% when labour was induced versus an increase of 3.4% to a rate of 7.5% in spontaneous labour. Conclusion In absolute numbers the rise in CS was most extensive in the group of women with a singleton fetus in vertex presentation between 37 and 42 weeks of gestation. Induction of labour rates and instrumental vaginal delivery rates remained constant during the past decade.

Timing of Induction of Labour for Post Maturity and Caesarean Section Patterns

A comparison of outcome versus gestation at induction of labour (IOL) for post maturity in three groups:40,41and 42 weeks. Design: Retrospective study of all 703 IOLs for post maturity over three-years. The main outcome being measured was recourse to emergency Caesarean section (Em LSCS) mode of delivery. Groups were compared. Setting: A District General Hospital with 8754 deliveries over the study period. The overall IOL rate was 18.8 . Result: Em LSCS rates break down as follows: 40th week; Primigravidae 25.7%, Multiparae 6.9%, Both 13.9% 41st week; Primigravidae 17.6%, Multiparae 6.4%, Both 10.6% 42nd week; Primigravidae 18.8%, Multiparae 11.3%, Both 15.2 No statistically significant benefit was demonstrated for either group at any gestation

Is there a useful cesarean birth measure? Assessment of the nulliparous term singleton vertex cesarean birth rate as a tool for obstetric quality improvement

This study was undertaken to assess the utility of the nulliparous term singleton vertex cesarean birth (NTSV CB) measure as a quality improvement tool for use at the hospital level. We prospectively collected data on all NTSV births in Sutter Health's 20 birthing units over a 3-year period, 2001 through 2003, totaling 41,416 births. Hospital rates of NTSV CB, obstetric practices, and infant outcomes were calculated and compared by using weighted logistic analyses. In addition, we examined the effect of maternal age on the NTSV CB measure by using direct standardization with US norms for nulliparous women. There was large variation noted in the NTSV CB rate among the 20 hospitals, with unadjusted rates ranging from 10.5% to 30.2%. Strong correlations were found between CB rates and labor induction rates (r = 0.57, P < .0001) and with early labor admission rates (r = 0.62, P < .0001). The strongest correlation was found between NTSV CB rates and a combined measure of induction and early labor admission (r = 0.73, P < .0001). Rates of term 5-minute Apgar score below 7 were not correlated with the NTSV CB rate. Hospital nulliparous maternal age distribution varied markedly and direct standardization led to significant changes in the NTSV CB rate. NTSV CB rate is strongly influenced by elective obstetric practices. The addition of an easily performed maternal age adjustment makes it the most promising CB quality measure for use at the hospital level.