Your SlideShare is downloading. ×
Preventing the first cesarean delivery
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×

Introducing the official SlideShare app

Stunning, full-screen experience for iPhone and Android

Text the download link to your phone

Standard text messaging rates apply

Preventing the first cesarean delivery

2,416
views

Published on

Preventing the first cesarean delivery

Preventing the first cesarean delivery

Published in: Health & Medicine

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
2,416
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
75
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Current CommentaryPreventing the First Cesarean DeliverySummary of a Joint Eunice Kennedy Shriver National Institute ofChild Health and Human Development, Society for Maternal-Fetal Medicine, and American College of Obstetricians andGynecologists WorkshopCatherine Y. Spong, MD, Vincenzo Berghella, MD, Katharine D. Wenstrom, MD, Brian M. Mercer, MD,and George R. Saade, MD points were identified to assist with reduction in cesar-With more than one third of pregnancies in the United ean delivery rates including that labor induction shouldStates being delivered by cesarean and the growing be performed primarily for medical indication; if doneknowledge of morbidities associated with repeat cesar- for nonmedical indications, the gestational age should beean deliveries, the Eunice Kennedy Shriver National Insti- at least 39 weeks or more and the cervix should be favor-tute of Child Health and Human Development, the able, especially in the nulliparous patient. Review of theSociety for Maternal-Fetal Medicine, and the American current literature demonstrates the importance of adher-College of Obstetricians and Gynecologists convened ing to appropriate definitions for failed induction anda workshop to address the concept of preventing the first arrest of labor progress. The diagnosis of “failed induc-cesarean delivery. The available information on maternal tion” should only be made after an adequate attempt.and fetal factors, labor management and induction, and Adequate time for normal latent and active phases ofnonmedical factors leading to the first cesarean delivery the first stage, and for the second stage, should bewas reviewed as well as the implications of the first allowed as long as the maternal and fetal conditions per-cesarean delivery on future reproductive health. Key mit. The adequate time for each of these stages appears to be longer than traditionally estimated. Operative vag-From the Pregnancy and Perinatology Branch, Eunice Kennedy ShriverNational Institute of Child Health and Human Development, National Insti- inal delivery is an acceptable birth method when indi-tutes of Health, Bethesda, Maryland; the Division of Maternal-Fetal Medicine, cated and can safely prevent cesarean delivery. Given theDepartment of Obstetrics and Gynecology, Jefferson Medical College of Thomas progressively declining use, it is critical that training andJefferson University, Philadelphia, Pennsylvania; the Division of Maternal-Fetal experience in operative vaginal delivery are facilitatedMedicine, Department of Obstetrics and Gynecology, Brown Alpert School ofMedicine, Women and Infants Hospital, Providence, Rhode Island; the Depart- and encouraged. When discussing the first cesareanment of Obstetrics & Gynecology, MetroHealth Medical Center Case Western delivery with a patient, counseling should include itsReserve University, Cleveland, Ohio; the Division of Maternal-Fetal Medicine, effect on future reproductive health.Department of Obstetrics & Gynecology, University of Texas Medical Branch, (Obstet Gynecol 2012;120:1181–93)Galveston, Texas; and the Publications and Executive Committees of the Societyfor Maternal-Fetal Medicine, Washington, DC. DOI: http://10.1097/AOG.0b013e3182704880This article is an executive summary of a Society for Maternal-Fetal Medicine, CEunice Kennedy Shriver National Institute of Child Health and HumanDevelopment, and American College of Obstetricians and Gynecologists workshop esarean delivery is the most commonly performedthat was held February 7–8, 2012, in Dallas, Texas. major surgery in the United States. Approxi-Dr. Spong, Associate Editor of Obstetrics & Gynecology, was not involved in mately one in three pregnancies is delivered by cesar-the review or decision to publish this article. ean, accounting for more than 1 million surgeries eachCorresponding author: Catherine Y. Spong, MD, Chief, Pregnancy and year.1 In 2007, 26.5% of low-risk women giving birthPerinatology Branch, NICHD, NIH, 6100 Executive Boulevard, Room 4B03 for the first time had a cesarean delivery.2 The HealthyMSC 7510, Bethesda, MD 20892; e-mail: spongc@mail.nih.gov. People target for 2020 is a cesarean delivery rate ofFinancial DisclosureThe authors did not report any potential conflicts of interest. 23.9% in low-risk full-term women with a singleton, vertex presentation. This is much higher than the© 2012 by The American College of Obstetricians and Gynecologists. Publishedby Lippincott Williams & Wilkins. never achieved target cesarean delivery rate of 15%ISSN: 0029-7844/12 for Healthy People 2010.3 The appropriate rate ofVOL. 120, NO. 5, NOVEMBER 2012 OBSTETRICS & GYNECOLOGY 1181
  • 2. cesarean delivery is not easily determined because it which may be preventable (Table 1). Importantly,varies according to multiple factors. Although “case there are very few absolute indications for cesareanmix adjustment” for these factors has been proposed, delivery such as complete placenta previa, vasa pre-there are limited data on which variables should be via, or cord prolapse. Most indications depend on theincluded in the adjustment when evaluating variations caregiver’s interpretation, recommendation, or actionbetween individuals or institutions. The primary cesar- in response to the developing situation, thereforeean delivery is defined as the first cesarean delivery. making them modifiable and likely target to lowerGiven its effect on subsequent pregnancies, an under- the cesarean delivery rate (Tables 2–4). Although eachstanding of the drivers behind the increase in primary individual indication for cesarean delivery makescesarean delivery rates, and renewed effort to reduce a finite contribution to the overall primary cesareanthem, may have a substantial effect on health care. delivery rate, a measurable reduction could result if Although the dramatic rise in the rate of cesarean concerted interventions were adopted to avoid eachdelivery since 1995 is attributable in part to an increase and all unneeded surgeries.in frequency of primary cesarean deliveries, it is also Patient and physician attitudes as well as theirthe result of a decline in attempted trials of labor after perceptions regarding the risks of vaginal deliverycesarean delivery. Of U.S. women who require an compared with cesarean delivery are other potentiallyinitial cesarean delivery, more than 90% will have modifiable factors. Undue concern about vaginala subsequent repeat cesarean delivery. Not only does delivery coupled with relative indifference regardingcesarean delivery increase the risk of maternal compli- the risks of cesarean delivery may lead to a decisioncations in the index pregnancy, including intraoper- that is not based on clinical evidence. Wheneverative complications, it has serious implications for cesarean delivery is planned or performed, the patientfuture gestations. Adhesions of the uterus, bowel, and should be advised of the short- and long-term risksbladder can result in trauma at surgery, whereas and benefits of the surgery both for herself and herabnormal placentation (placenta previa, accreta, incre- offspring, in the present and future. The corollary ista, percreta) and uterine rupture can be catastrophic for that the risks associated with vaginal delivery shouldboth mother and neonate.4 Given the risks associated be presented in an objective and unbiased manner.with the initial cesarean delivery and its implications for The indication for the surgery should be included insubsequent pregnancies, the most effective approach to the consent and documented in the patient record.reducing overall morbidities related to cesarean deliv- A cesarean delivery that is performed without anery is to avoid the first cesarean delivery. Incidences of accepted indication should be labeled as such, ie,maternal as well as perinatal morbidity and mortality “nonindicated cesarean delivery.” The term “electiveshould be kept to the lowest level achievable. cesarean delivery” should be avoided.5 To synthesize the available information regardingfactors leading to the first cesarean delivery, including Table 1. Major Indications for Primary Cesareanobstetric, maternal, and fetal indications for cesarean Deliverydelivery, labor management and induction practices,and nonmedical factors, the Eunice Kennedy Shriver Stage Indication %National Institute of Child Health and Human Devel- Prelabor Malpresentation 10–15*opment (NICHD), the Society for Maternal Fetal Med- Multiple gestation 3icine, and the American College of Obstetricians and Hypertensive disorders 3Gynecologists convened a workshop on February 7–8, Macrosomia 32012. Workshop participants also reviewed the implica- Maternal request 2–8 In labor First-stage arrest 15–30*tions of the first cesarean delivery on future reproductive Second-stage arrest 10–25health and considered recommendations for practice, Failed induction 10opportunities for patient and community education, Nonreassuring fetal heart rate 10and potential areas for research with the goals of deter- Some indications may occur both prelabor and in labor.mining the scope of the problem and identifying oppor- * Percentage of all cesarean deliveries that have this as a primarytunities to reduce unnecessary first cesarean deliveries. indication. Data from Zhang J, Troendle J, Reddy UM, Laughon SK, Branch DW, Burkman R, et al. Contemporary cesarean deliveryEXAMINING INDICATIONS FOR PRIMARY practice in the United States. Am J Obstet GynecolCESAREAN DELIVERY 2010;203:326.e1–10; and Barber EL, Lundsberg LS, Belanger K, Pettker CM, Funai EF, Illuzzi JL. Indications contributing toThere are numerous obstetric, fetal, and maternal the increasing cesarean delivery rate. Obstet Gynecolindications for primary cesarean delivery, some of 2011;118:29–38.1182 Spong et al Preventing the First Cesarean Delivery OBSTETRICS & GYNECOLOGY
  • 3. Table 2. Selected Potentially Modifiable Obstetric Indications for First Cesarean Delivery Effect on Prevention Diagnostic of First CesareanIndication Accuracy* Delivery† Preventive StrategiesFailed induction Limited Large See Table 5 and Figure 1Arrest of labor Limited Large See Table 5 and Figure 3Multiple gestation High Small Prevent multiple gestations: encourage single embryo transfer Safe trial of labor: training for vaginal twin delivery, simulation for cephalic version, or breech extraction of second twinPreeclampsia High Small Education: preeclampsia is not an indication for cesarean deliveryPrior shoulder dystocia Limited Small Improved documentation as to prior shoulder dystocia Education regarding risk of recurrence based on estimated fetal weight Prior shoulder dystocia is not an absolute indication for cesarean deliveryPrior myomectomy Limited Small Improved documentation of prior myomectomy Education regarding impact of myomectomy on deliveryPrior third-degree or fourth-degree High Small Education: not an absolute indication for cesarean laceration, prior breakdown of delivery repair, fistula Education: limited ability to predict recurrenceMarginal and low-lying High Small Education: attempt at vaginal delivery acceptable as placentation long as placenta is 1 cm or more from internal os38* Diagnostic criteria accuracy: how readily and accurately cases can be diagnosed. For example, the ability to diagnose multiple gestations is high, whereas the ability to identify all cases of shoulder dystocia is limited as a result of subjectivity of the definition.† Effect on prevention of first cesarean delivery: large means that modification of indication (eg, arrest of labor) could lead to a large decrease in cesarean deliveries. Small means that modification of indication (eg, prior shoulder dystocia) could lead to a small decrease in cesarean deliveries. In addition to monitoring and providing feed- induce labor for medical or nonmedical indications,back to clinicians regarding their indications for and labor management style, the diagnosis and manage-rates of primary cesarean deliveries, institutions ment of arrest disorders in the first and second stagesshould identify those occurring without an accepted of labor, the use of labor neuroaxial anesthesia, themedical indication. Of those with specific indications, use of operative vaginal delivery, and evaluation ofattention should be paid to cesarean deliveries fetal factors as well as nonmedical indications mayoccurring after labor inductions, those labeled as for affect the potential for successful vaginal delivery.“nonreassuring fetal status,” and those occurring forlabor arrest or “failed induction” without meeting Induction of Laboraccepted criteria (Table 5). A classification system is The overall likelihood of vaginal delivery is lowerneeded to track cesarean deliveries, compare rates after labor induction than after spontaneous labor,between practices and over time, perform audits, pro- especially when labor induction is attempted invide feedback, and identify areas for potential inter- a nulliparous woman with an unfavorable cervix.vention.6 Although not uniquely designed for Institutions should have a clear policy regarding laborprimary cesarean deliveries, the Robson classification induction, including a list of acceptable indications,is an example of a simple method that allows com- and should specify the definitions of a favorableparison of cesarean delivery rates between practices cervix, options for cervical ripening in the presenceas well as over time.7–9 of an unripe cervix, oxytocin infusion protocols, and criteria for the diagnosis of failed induction. LaborLABOR MANAGEMENT PRACTICES AND induction with an unfavorable cervix should not bePRIMARY CESAREAN DELIVERY undertaken unless delivery is indicated for clearAntepartum and intrapartum management decisions maternal or fetal benefit. Any time induction iscan have a profound effect on the individual patient’s undertaken, it should be clear that the goal is vaginallikelihood of cesarean delivery. The decision to delivery.VOL. 120, NO. 5, NOVEMBER 2012 Spong et al Preventing the First Cesarean Delivery 1183
  • 4. Table 3. Selected Potentially Modifiable Fetal Indications for First Cesarean Delivery Diagnostic Effect on Prevention of FirstIndication Accuracy* Cesarean Delivery† Preventive StrategiesMalpresentation High Large External cephalic versionNonreassuring antepartum or Moderate Large Education regarding correct interpretation intrapartum fetal surveillance and management (Fig. 2) Confirmatory tests (eg, scalp stimulation) Intrauterine resuscitative measures (eg, IVF, position change, oxygen, etc)Macrosomia Limited Small Screen for and treat diabetes; limit weight gain in pregnancyMalformations, eg, NTD, SCT, Moderate Small Anecdotal for indication EXIT procedure, hydrops Education: cesarean delivery not indicated for abdominal wall defects Multidisciplinary education of subspecialists and counseling of patientsIVF, in vitro fertilization; NTD, neural tube defects; SCT, sacrococcygeal teratoma; EXIT, ex utero intrapartum treatment.* Diagnostic criteria accuracy: how readily and accurately cases can be diagnosed. For example, the ability to diagnose malpresentation is high, whereas the ability to identify macrosomia is limited. Moderate accuracy is between high and limited.† Effect on prevention of first cesarean delivery: large means that modification of indication (eg, malpresentation) could lead to a large decrease in cesarean deliveries. Small means that modification of indication (eg, malformations) could lead to a small decrease in cesarean deliveries. Because an unfavorable cervix can negatively Pragmatically, although the potential maternal andaffect the labor course and increase the potential for fetal risks related to induction with an unfavorablecesarean delivery, this factor should be considered in cervix should be incorporated into the overall risk–decision-making regarding the method of labor induc- benefit evaluation when considering medically indi-tion. However, the decision for induction should be cated labor induction, the decision to proceed withconsidered first and should be separate from the induction should be made independent of the condi-decision about whether to use cervical ripening. tion of the cervix and based on the specific indicationTable 4. Selected Potentially Modifiable Maternal Indications for First Cesarean Delivery Effect on Diagnostic Prevention of Criteria First CesareanIndication Accuracy* Delivery† Preventive StrategiesObesity (BMI greater than or equal to High Small Weight loss preconception, and limited weight 30 kg/m2) gain in pregnancy Education: obesity is not an indication for cesarean delivery and is a poor predictor of cesarean deliveryInfection (HSV, HCV, HIV) High Small HIV treatment to minimize viral loadCardiovascular disease (acute High Small Education: not an independent indication for HTN crisis, cardiomyopathy, cesarean delivery pulmonary HTN, cerebral aneurysm, CVA)Inadequate pelvis Limited Small Education: in general, not an indication for cesarean deliveryRequest (no maternal, obstetric, Not applicable Small Education of patient and provider regarding acute or fetal indication) complications and long-term risks, benefits, and effect of cesarean delivery on mother and newborn; specific education on fear of laborBMI, body mass index; HSV, herpes simplex virus; HCV, hepatitis C virus; HIV, human immunodeficiency virus; HTN, hypertension; CVA, cerebrovascular accident.* Diagnostic criteria accuracy: how readily and accurately cases can be diagnosed. For example, the ability to diagnose infection is high, whereas the ability to identify inadequate pelvis is limited as a result of subjectivity of the definition.† Effect on prevention of first cesarean delivery: small means that modification of indication (eg, infection) could lead to a small decrease in cesarean deliveries.1184 Spong et al Preventing the First Cesarean Delivery OBSTETRICS & GYNECOLOGY
  • 5. Table 5. Definitions of Failed Induction and Arrest tion, and the expectation that well-defined criteria be Disorders met before cesarean delivery is performed for failureFailed induction of labor of induction or failure of progress in labor, may Failure to generate regular (eg, every 3 min) contractions actually prevent many unnecessary first cesarean and cervical change after at least 24 h of oxytocin deliveries. During this evaluation, it is important to administration, with artificial membrane rupture if differentiate between “failed induction” and “arrest of feasible labor” in the first stage. The diagnosis of failed induc-First-stage arrest 6 cm or greater dilation* with membrane rupture and no tion should be reserved for those women who have cervical change for not achieved regular (eg, every 3 minutes) contrac- 4 h or more of adequate contractions (eg, .200 tions and cervical change after at least 24 hours of Montevideo units) or oxytocin administration with artificial membrane rup- 6 h or more if contractions inadequate ture if feasible (after completion of cervical ripening, ifSecond-stage arrest No progress (descent or rotation) for performed; Table 5; Fig. 1). Studies have shown that 4 h or more in nulliparous women with an epidural more than half of the women undergoing labor induc- 3 h or more in nulliparous women without an epidural tion remain in the latent phase for at least 6 hours, and 3 h or more in multiparous women with an epidural nearly one fifth remain in the latent phase for 12 hours 2 h or more in multiparous women without an epidural or longer.11 In a multicenter study, nearly 40% of the* Since women may still be in latent labor, additional time and women still in the latent phase after 12 hours of oxy- interventions may be needed in order to diagnose an arrest of active labor before 6 cm dilatation (see Figure 1 for suggested tocin and membrane rupture successfully delivered management). vaginally. These data suggest that induction should not be defined to have failed in the latent phase unless oxytocin has been administered for at least 24 hours(s). There is no single definition used to differentiate or for 12 hours after membrane rupture.12,13 Numer-a favorable (“ripe”) from an unfavorable (“unripe”) ous approaches to induction and cervical ripeningcervix whether in research or in clinical practice. In have been published, and no single approach is con-general, the Bishop’s score has most often been used sidered superior to all others. Individual circumstan-to describe cervical ripeness. A Bishop’s score greater ces should be considered for each patient. Thethan 8 generally confers the same likelihood of vagi- algorithm offered in Figure 1 provides a generalnal delivery with induction of labor as that after spon- approach once the decision has been made to proceedtaneous labor and thus has been considered to with labor induction.indicate a favorable cervix.10 Conversely, a Bishop’s There is much debate as to how long inductionscore of 6 or less has been used to denote an unfavor- should be allowed to continue and whether it isable cervix in many studies and has been associated appropriate to “rest” the patient who does not progresswith a higher risk of cesarean delivery when labor is after 12 or more hours of induction but who does notinduced compared with spontaneous labor. Because otherwise have a maternal or fetal reason for immediatethe Bishop’s score was originally developed to predict delivery. In cases in which induction is undertaken forthe likelihood of multiparous women at term to enterspontaneous labor, making it less predictive of out-come after labor induction in nulliparas, the effects Box 1. Quality Measures to Track and Provideof maternal parity and gestational age were also con- Feedback for Each Obstetrician–Gynecologistsidered during the workshop. Cervical ripening may Physician*be considered when there is a medical indication forinduction. Because inductions without medical indica-  Rate of nonmedically indicated cesarean deliverytion should not be done with an unripe cervix, cervi-  Rate of nonmedically indicated inductioncal ripening would not be an option (Fig. 1). Although  Rate of labor arrest or failed induction diagnosed with-cervical ripening agents have generally not been dem- out meeting accepted criteriaonstrated to reduce the likelihood of cesarean delivery  Rate of cesarean deliveries for nonreassuring fetalin prospective interventional trials, their use can affect heart rate by Eunice Kennedy Shriver National Insti-the duration of labor. tute of Child Health and Human Development Because the goal of labor induction is vaginal category14delivery, adequate time to enter into or progress inlabor should be allowed, provided the mother and *For singleton gestation, vertex presentation, at 37 0/7 to 41 6/7 weeks of gestation.neonate are stable. The prudent use of labor induc-VOL. 120, NO. 5, NOVEMBER 2012 Spong et al Preventing the First Cesarean Delivery 1185
  • 6. Induction Oxytocin with regular frequent contractions Cervical change No cervical change from baseline from baseline At least 6 cm Less than 6 cm Rupture of membranes Rupture of membranes safe and feasible not safe or not feasible Rupture of membranes Contractions at not safe or not feasible At least 3 cm Less than 3 cm; fetal least every 3 minutes heart tracing reassuring; for at least 6 hours, patient stable but no further Administer oxytocin cervical change at least 24 hours Options: Mechanical cervical Rupture of membranes Rupture of membranes Rupture of membranes ripening not safe or not feasible safe and feasible not safe or not feasible Pharmacologic cervical ripening with alternate agent Consider cesarean Consider double setup Consider resting delivery for attempted rupture patient overnight of membranes Rupture of membranes Cervical change No cervical change Inadequate Rupture of membranes despite adequate contractions; no not feasible contractions for at cervical change least 4 hours for at least 6 hours Consider cesarean Continue labor deliveryFig. 1. Algorithm for induced labor.Spong. Preventing the First Cesarean Delivery. Obstet Gynecol 2012.specific maternal or fetal conditions that can worsen time and whose membranes remain intact (Table 5;with time, stopping the induction is not an appropriate Fig. 1). An arrest disorder should not be confused withoption. Examples of such cases include preeclampsia, failed induction. The diagnosis of an arrest disorder infetal growth restriction, diabetes, and ruptured mem- women undergoing induction should not be madebranes. On the other hand, induction is sometimes unless the woman has entered the active phase of labor,undertaken when neither the maternal nor fetal condi- requiring that there be documented cervical changetion is expected to deteriorate rapidly. An example is preceding the arrest in dilation (Table 5). Once 6-cminduction at 41 weeks of gestation. Despite this being cervical dilation is reached and the active phase isa common obstetric dilemma, guidance available from entered, labor progress during induction is similar toprofessional organizations does not provide clarity.15–17 the patient in spontaneous labor. However, the dura-Published trials allowed cervical ripening over a period tion of the phase before 6-cm dilation is longer inranging from a single dose to several doses over days. women undergoing induction.17In a trial of the Maternal-Fetal Medicine Units Net-work, the study design specified at least 24 hours from LABOR-MANAGEMENT STYLEstart of oxytocin before declaring a failed induction. All It has been suggested that the widely varying rates oftrials have found good outcomes in the induction group cesarean delivery among health care providers may bedespite waiting for at least 24 hours before failed induc- the result of different labor management styles. Admis-tion was declared. It is also important to note that in all sion of women in the early latent phase of labor (eg,induction trials, rupture of membranes was undertaken less than 3 cm dilated) has been associated with higheras soon as feasible and safe. Based on this indirect evi- cesarean delivery rates. However, it is unclear whetherdence, it is considered appropriate to temporize before the admission in early labor itself increases the risk fordeclaring that an induction has failed in women being cesarean delivery or if women requiring admissioninduced for conditions that are not likely to worsen with earlier in labor are actually more likely to have an1186 Spong et al Preventing the First Cesarean Delivery OBSTETRICS & GYNECOLOGY
  • 7. abnormal labor course (eg, abnormal contraction differentiate between the diagnostic criteria for arrestpattern resulting in excessive pain and slower progress disorders that occur after spontaneous labor comparedin early labor, foreshadowing a subsequent arrest with labor induction. Pragmatically, arrest disorders indisorder). Hospital admission does provide more time spontaneously laboring women are defined by clinicalto monitor labor progress and fetal well-being as well findings noted after admission. In both spontaneous asas to implement interventions to facilitate labor. well as induced labor, the diagnosis of an arrestHowever, early admission could also give the impres- disorder should not be made before the patient hassion of a long labor and result in earlier abandonment entered into the active phase. The definitions of arrestif progress is not deemed adequate or because of disorders outlined in Table 5 vary somewhat frompressure from the patient or family. Although it is published criteria10 in recognition of more recent find-prudent to avoid unneeded admissions (eg, before 3 ings regarding labor progress that challenge our long-cm of dilatation) and interventions (eg, augmentation, held practices based on the Friedman curve. Forartificial membrane rupture), there is limited informa- example, the acceleration phase in active labor maytion regarding the direct effect of these practices on not begin until approximately 6-cm dilation ratherprimary cesarean delivery rates. than the previously recognized 4-cm cutoff, and mul- Provider type (eg, physician, certified nurse mid- tiparous women appear to have a steeper accelerationwife) may also be related to labor outcomes. Whether phase than previously thought.22this relationship is causal or merely by association is Data needed to establish the normal range for thenot clear.19–21 It is possible that differences in the char- duration of the latent phase are not readily availableacteristics and expectations of women seeking differ- because the onset of the latent phase in most womenent health care provider types may also affect the in spontaneous labor occurs outside the hospital andoutcome; for example, the woman interested in deliv- therefore cannot be accurately determined. Availableering with a midwife or other low-risk health care evidence suggests that the duration of the latent phaseprovider may have an inherently different risk of is not different between nulliparous and multiparouscesarean delivery than one who prefers the care of women, a finding that contrasts with the overall lengthan obstetrician or maternal-fetal medicine subspecial- of the first and second stages of labor.22 Based on dataist. Despite this, the same defined criteria for labor from the safe labor consortium, nulliparous women inarrest and prolonged labor should be used regardless spontaneous labor entering the hospital have a medianof health care provider or patient type. duration of 6 hours (95th percentile of 15.7 hours) to reach the active phase of labor (6-cm dilation) if theyDIAGNOSIS OF ARREST DISORDERS enter the hospital at 2-cm dilation, and 4.2 hours (95thThe concept of a prolonged or “protracted” first or percentile 12.5 hours) if they enter at 3 cm.22 Nullip-second stage of labor should be considered distinct arous women admitted in spontaneous labor withfrom that of an arrest disorder. Progress in the first a cervix between 2 and 4 cm may not change theirstage should not be based solely on cervical dilation cervix for up to 7 to 6 hours, respectively.22but must also take into consideration change in cervi- The safe labor consortium analyzed the durationcal effacement and fetal station. Similarly, progress in of labor in 62,415 women with a term singletonthe second stage involves not only descent, but also pregnancy and a normal outcome and developedrotation of the fetal head as it traverses the maternal contemporary partograms for labor.22 Labor in nul-pelvis. Recognition of arrest of labor in the first or liparous women took longer than expected based onsecond stage of labor (Table 5) provides an opportu- the Friedman curves. The investigators found thatnity to reassess the maternal and fetal condition, to labor can take more than 6 hours to progress fromcounsel the woman about the ongoing potential for 4 cm to 5 cm and more than 3 hours to progress fromsuccessful vaginal delivery, and to address the mater- 5 cm to 6 cm. The median duration of the activenal and perinatal risks of continued labor. However, phase, from 6 cm to complete cervical dilation, was“protracted labor” alone should not be the sole 2.1 hours in nulliparous women and 1.5 hours inindication for an operative vaginal or cesarean multiparous women, with 95th percentiles of 8.6 hoursdelivery if progress is being made and the maternal and 7.5 hours, respectively. The median and 95th per-and fetal status are reassuring. centiles for the cervical change before 6 cm are sim- Although the timing of labor onset in the patient ilar for nulliparous and multiparous women. After 6entering spontaneous labor at home may be less clear, cm, multiparous women had a slightly faster laborand the progress of labor before arrival to the hospital than nulliparous women. These data suggest that thecannot be accurately assessed, there is no reason to historical criteria defining normal labor progress—VOL. 120, NO. 5, NOVEMBER 2012 Spong et al Preventing the First Cesarean Delivery 1187
  • 8. cervical change of 1.2 cm/h for nulliparous women Table 6. Duration of Each Centimeter Change inand 1.5 cm/h for multiparous women—are no longer Cervical Dilatation for Nulliparousvalid. Women With Spontaneous Onset of As for the second stage of labor, the data from the Labor*safe labor consortium showed the median duration Cervical Change (cm) Median (h) 95th Percentile (h)(95th percentile) with epidural analgesia to be 1.1 (3.6),0.4 (2.0), and 0.3 (1.6) hours for nulliparous, primipa- 3–4 1.8 8.1 4–5 1.3 6.4rous, and multiparous women, respectively, and 0.6 5–6 0.8 3.2(2.8), 0.2 (1.3), and 0.1 (1.1) hours without an epidural.21 6–7 0.6 2.2Table 6 shows the median and 95th percentile duration 7–8 0.5 1.6for each centimeter change in nulliparous women in 8–9 0.5 1.4spontaneous labor. 9–10 0.5 1.8 * Modified from Zhang J, Landy HJ, Branch DW, Burkman R, Haberman S, Gregory KD, et al. Contemporary patterns ofLABOR ANALGESIA spontaneous labor with normal neonatal outcomes. Obstet Gynecol 2010;116:1281–7.Although it has been suggested that the use ofneuraxial analgesia (epidural, spinal, or combinedspinal–epidural) may prolong the latent phase of performed by an experienced health care practitioner.spontaneous labor, numerous trials have failed to find Training programs should have readily availablean increase in cesarean delivery with neuraxial anal- skilled operators to teach these procedures andgesia either during labor induction or after spontane- mechanisms in place to provide training, includingous labor.23–25 As such, neuraxial analgesia should not in actual cases as well as by simulation.be withheld or delayed because of concerns regardingthe risk of cesarean delivery. EVALUATION OF FETAL STATUS BEFORE AND DURING LABOROPERATIVE VAGINAL DELIVERY Electronic fetal heart monitoring remains the main-Forceps and vacuum-assisted operative vaginal deliv- stay for assessment of fetal status during labor and isery may avert a cesarean delivery when maternal often used to decide on the mode of delivery inexpulsive forces are inadequate or expedited delivery a complicated pregnancy (Fig. 2). Continuous intra-is needed.26 Many studies, including some that fol- partum fetal heart rate monitoring has been used inlowed the offspring up to 18 years of age, have dem- more than 85% of deliveries in the United States foronstrated that neonates delivered by operative vaginal more than a decade.31 However, despite the expec-delivery typically have a normal newborn transition tation that continuous intrapartum fetal heart rateperiod and normal long-term outcomes.27–30 Compar- monitoring would improve perinatal outcomes anding the reported rates of cesarean delivery with oper- the concomitant rise in cesarean deliveries, there hasative vaginal delivery among U.S., Canadian, and been no reduction in the rate of cerebral palsy sinceEuropean practices, it becomes clear that higher rates its introduction in the United States and elsewhere.of operative vaginal delivery are often associated with Although studies have found no benefit of continu-lower cesarean delivery rates, and vice versa. ous monitoring over intermittent auscultation in low-Although plausible, a cause-and-effect relationship risk women, intermittent auscultation requires one-has not been established. to-one nursing throughout labor and may not be Although operative vaginal delivery is acceptable appropriate in high-risk women or when there arein appropriate circumstances, it requires an operator fetal heart rate abnormalities detected by ausculta-who understands the indications and prerequisites and tion. Although it is reasonable to provide intermit-is skilled in the technique. For this reason, the tent auscultation for low-risk women, guidelinesdiminishing training and experience in operative defining appropriate candidates, the required fre-vaginal delivery nationally is of concern. Important quency of auscultation, and criteria for conversionsteps in providing initial training and in maintaining to continuous fetal heart rate monitoring should beskills include not only increased supervised training in place and enforced.during residency and supplemental training and skill Important limitations in the interpretation ofmaintenance simulations, but recognition by both continuous fetal heart rate monitoring include con-patients and physicians that operative vaginal delivery siderable interobserver variability in the identificationis safe and can reduce perinatal morbidities when of fetal heart rate patterns likely to be associated with1188 Spong et al Preventing the First Cesarean Delivery OBSTETRICS & GYNECOLOGY
  • 9. Assessment of intrapartum FHR tracingFig. 2. Assessment of intrapartum Category I Category II* Category IIIfetal heart rate monitoring. *Giventhe wide variation of fetal heart rate Start intrauterine Routine management Evaluation and(FHR) tracings in Category II, this surveillance; resuscitativealgorithm is not meant to represent confirmatory test (for measures†;assessment and management of all example, scalp prepare for deliverypotential FHR tracings but provide an stimulation)action template for common clinicalsituations. †Intrauterine resuscitativemeasures may include oxygen sup- FHR accelerations Absent FHR If not improved, or moderate FHR accelerations and consider promptplementation, position change, intra- variability absent or minimal delivery‡venous fluids, stopping oxytocin, FHR variabilitytocolysis, and amnioinfusion. ‡Timingand mode of delivery based on feasi- Continue surveillance Intrauterinebility and maternal-fetal status. Modi- and intrauterine resuscitativefied from Management of intrapartum resuscitative measures†fetal heart rate tracings. Practice Bul- measures†letin No. 116. American College ofObstetricians and Gynecologists. Ob- If not improved orstet Gynecol 2010;116:1232–40. FHR tracing progressesSpong. Preventing the First Cesarean to Category III,Delivery. Obstet Gynecol 2012. consider delivery‡fetal acidosis and the fact that many patterns have Fetal heart rate acceleration in response to fetala low positive predictive value for adverse outcomes. scalp stimulation is supportive evidence suggestingIn 2008, the NICHD revised the guidelines for the absence of metabolic acidemia. Although fetalinterpretation of fetal heart rate patterns, creating scalp sampling was previously used to determinea three-tiered interpretation system. Category I fetal scalp microcapillary pH, the hardware needed forheart rate tracings are strongly predictive of normal bedside fetal scalp pH assessment is no longer readilyfetal acid-base status and are considered “normal.” available in the United States. The efficacy of otherCategory III fetal heart rate patterns are predictive ancillary technologies (eg fetal pulse oximetry, fetalof abnormal fetal acid-base status at the time of obser- electrocardiographic ST-segment analysis, computer-vation and are considered “abnormal.” The interme- ized fetal heart rate pattern interpretation) to improvediate Category II fetal heart rate patterns include neonatal outcome has not been confirmed. Until addi-those that cannot be classified as Category I or III.14 tional effective technologies become available, it is un-The NICHD recommendations do not specify any likely that the rate of cesarean delivery for fetal heartparticular intervention for Category I tracings but rate abnormalities will be reduced substantially.do support prompt evaluation of Category III heart It is important to remember that any test thatrate patterns. Although interventions to resolve an depends on human interpretation will be subject toabnormal Category III fetal heart rate pattern may the pressures exerted on the individual making thehelp to avoid unneeded cesarean delivery, expedi- decision and the individual’s responses to the envi-tious delivery is recommended if these efforts are ronment. This will lead to either higher false-nega-unsuccessful (Fig. 2). The intermediate Category tive or higher false-positive test results dependingII fetal heart rate pattern requires a heightened on whether the decision-maker fears more thelevel of attention but does not by itself require implications of a mistaken diagnosis or the implica-immediate delivery; rather, evaluation and con- tions of missing a diagnosis, respectively. In the casetinued surveillance and re-evaluation are recom- of electronic fetal monitoring, the major implicationmended. Maneuvers to improve uteroplacental of a false-positive interpretation is a potentiallyperfusion (eg, adjustment of oxytocin infusion unnecessary operative delivery, but the implicationrate, administration of maternal oxygen, change of a false-negative interpretation is an adverse out-of maternal position, treatment of maternal hypo- come for the fetus, along with its associated conse-tension) may result in reversion to a Category I quences to the decision-maker and hospital. Evenpattern. if one believes that continuous fetal heart rateVOL. 120, NO. 5, NOVEMBER 2012 Spong et al Preventing the First Cesarean Delivery 1189
  • 10. monitoring may have prevented some adverse Box 2. Key Pointsoutcomes, the evidence is overwhelming that ithas caused many more unnecessary interventions  A cesarean delivery that is performed without anoverall. The result is a rise in cesarean delivery accepted indication should be labeled as such, ie, “nonindicated cesarean delivery.” The term ”electiverates, which has led to an increased incidence of cesarean delivery” should be avoided.subsequent placenta accreta and associated mater-nal morbidities and mortality. When discussing  Labor induction should be performed only for medical indication; if done for nonmedical indications, thecontinuous fetal heart rate monitoring, the fetus gestational age should be 39 weeks or more, and thewho was “saved” is frequently held as proof of cervix should be favorable (Bishop score more than 8),benefit of this technology, but the many more especially in the nulliparous patient.women who underwent unnecessary procedures,  The diagnosis of failed induction should only be madehad significant morbidity or even died as a result after an adequate attempt. Failed induction is definedof a false-positive interpretation are rarely mentioned. as failure to generate regular (eg, every 3 minutes)Importantly, the fact that the risks of cesarean delivery contractions and cervical change after at least 24are cumulative over future pregnancies is frequently hours of oxytocin administration with artificial mem- brane rupture if feasible.overlooked. Given that interpretation of the fetal heart rate  Adequate time for normal latent and active phases ofcan be subjective, it is important that hospitals the first stage, and for the second stage, should be allowed unless expeditious delivery is medically indi-institute some form of quality control for operative cated (Table 5; Figs. 1 and 3).deliveries with nonreassuring fetal heart rate as theindication (Box 1). Including the fetal heart rate  In the presence of reassuring maternal and fetal sta- tus, the diagnosis of arrest of labor should not becategory in the indication should be expected. In made until adequate time has elapsed. This includesthe case of an indication with a Category II pattern, greater than 6 cm dilation with membrane ruptureconfirmatory testing, if any, should be documented, and 4 or more hours of adequate contractionssuch as a negative response to scalp stimulation (eg, greater than 200 Montevideo units) or 6 hoursor minimal variability. Regular audits and reports or more if contractions inadequate with no cervical change for first-stage arrest. For second-stage arrest,can be provided to the staff with the rates of oper- no progress (descent or rotation) for more than 4ative deliveries according to indications and stage hours in nulliparous women with an epidural, moreof labor. than 3 hours in nulliparous women without an epi- dural, more than 3 hours in multiparous women with an epidural, and more than 2 hours in multiparousNONMEDICAL FACTORS women without an epidural should be considered, with no cesarean delivery for this indication beforeThe relative safety of cesarean delivery has lowered these time limits (Table 5).both patient and physician apprehension regarding  Intermittent auscultation, done appropriately, is anthe risk of such surgery, especially in the face of acceptable method for labor management in low-riskborderline fetal heart rate abnormalities, protracted patients without heart rate abnormalities.labor or arrest disorders, or after the development of  In the patient with moderate fetal heart rate variability,obstetric or medical complications. In general, the other findings have little association with neurologicusual concerns regarding major surgery do not seem damage or acidosis.to apply as emphatically to cesarean delivery as toother operations. This is most evident among patients  Medically indicated operative vaginal delivery is an acceptable birth method. Given the currentrequesting a nonmedically indicated cesarean delivery rates, it is critical that training and experienceand physicians who acquiesce to such requests. in operative vaginal delivery are augmented andPatient perception and education, societal attitudes, encouraged.and social media all play a role.32 In addition to con-  Doctors who are salaried and participate in profit-shar-sidering the risk of the first cesarean delivery, physi- ing, thus reducing the financial incentive to limit thecians and patients should be made aware of the time spent managing labor, have lower cesarean deliv-potential complications resulting from repeated sur- ery rates.geries both for the mother (eg, adhesions, bowel or  When discussing the first cesarean delivery withbladder trauma, abnormal placentation including a patient, counseling should include its effect on sub-placenta accreta, uterine rupture, hysterectomy) and sequent pregnancy risks such as uterine rupture andthe fetus (eg, delayed delivery resulting from exten- placental implantation abnormalities including pla- centa previa and accreta.sive adhesions).1190 Spong et al Preventing the First Cesarean Delivery OBSTETRICS & GYNECOLOGY
  • 11. Spontaneous labor* 3–5.9 cm At least 6 cmFig. 3. Algorithm for spontaneous No cervical change Cervical change No cervical change Cervical changelabor. *Consider outpatient manage-ment of uncomplicated labor until at Supportive care† Continue labor Rupture of membranes Continue laborleast 3 cm dilated or fetal membranerupture occurs. †Continued observa- Cervical change No cervical change Inadequatetion in latent phase, with augmenta- despite adequate contractions; notion as indicated. Discharge may be contractions for at cervical changeappropriate if labor subsides, mem- least 4 hours for at least 6 hoursbranes remain intact, and maternaland fetal status remain stable. Consider cesareanSpong. Preventing the First Cesarean Continue labor deliveryDelivery. Obstet Gynecol 2012. Institutional factors, such as time constraints for Patient expectations, the medical–legal climate,scheduling on the labor and delivery unit, varying and practice patterns regarding intrapartum manage-operating room staff availability, and the inability to ment need to be addressed if the rate of primarysupport prolonged inductions with resources and cesarean delivery is to be reduced. Importantly, thespace that may be scarce all play a role in the misperception among reproductive-age women thatdecision to proceed to cesarean delivery. Physician labor and vaginal delivery can harm the neonate,factors such as fatigue, workload, and anticipated whereas cesarean delivery ensures a normal out-sleep deprivation likely also affect decision-making. come, must be recognized and corrected. Given theSeveral studies have suggested that cesarean delivery implications of primary cesarean delivery on bothrates are influenced by the “leisure incentive”; when pregnancy complications and subsequent deliveries,the health care provider can go to sleep or go home it is important to institute practice management thatafter the delivery, the cesarean delivery rate, espe- limits performance of the first cesarean deliverycially cesarean deliveries performed for “dystocia” (Table 5).(prolonged or dysfunctional labor) and “fetal intoler-ance of labor,” increases.33,34 Financial incentivesand disincentives related to work efficiency and staff- CONCLUSIONSing workload may also tilt the scale toward more Although numerous factors contribute to the primaryliberal performance of scheduled cesarean deliveries. cesarean delivery rate, the clinician’s ability to modifyGiven the time required to monitor a complicated some of these and mitigate others is the first steplabor, there is a financial disincentive to persevere toward lowering the primary cesarean delivery ratewhen labor does not proceed efficiently or if border- (Tables 2–5; Box 2). The available information online fetal heart patterns are present. Evidence sug- maternal and fetal factors, labor management andgests that doctors who are salaried and participate induction, and nonmedical factors leading to the firstin profit-sharing, thus reducing the financial incen- cesarean delivery as well as the implications of thetive to limit the time spent managing labor, have first cesarean delivery on future reproductive healthlower cesarean delivery rates.14 are reviewed and critical key points were identified The current medical–legal climate has also made (Box 2). The implications of a cesarean delivery ratewaiting for a vaginal delivery less attractive to many of 30% or more have tremendous effects on the med-physicians when labor is not proceeding smoothly. In ical system as well as on the health of women andmany centers, the number of cesarean deliveries per- children. It is essential to embrace this concern andformed for “nonreassuring fetal status” has increased provide guidance on strategies to lower the primarymore than any other indication despite the fact that cesarean delivery rate. Education regarding the nor-the number of women classified as high risk has not mal labor course and the implications of first cesareanincreased concomitantly.35,36 All of these factors are delivery may allow women and their health care pro-compounded by the belief among many patients that viders to avoid practices that increase the potential forcesarean delivery is safer for the fetus.37 unneeded first cesarean deliveries.VOL. 120, NO. 5, NOVEMBER 2012 Spong et al Preventing the First Cesarean Delivery 1191
  • 12. REFERENCES women: relationship to maternal and perinatal outcome. Am J Obstet Gynecol 2009;201:357.e1–7. 1. Hamilton BE, Martin JA, Ventura SJ. Births: preliminary data for 2009. Vol. 59, no 3. Hyattsville (MD): National Center for 19. Hatem M, Sandall J, Devane D, Soltani H, Gates S. Midwife- Health Statistics; 2010. led versus other models of care for childbearing women. The Cochrane Database of Systematic Reviews 2008, 2. Healthy People 2020, maternal, infant, and child health. Avail- Issue 4. Art. No.: CD004667. DOI: 10.1002/14651858. able at: www.healthypeople.gov/2020/topicsobjectives2020/ CD004667.pub2. objectiveslist.aspx?topicid=26. Retrieved April 30, 2012. 20. Rooks JP, Weatherby NL, Ernst EK, Stapleton S, Rosen D, 3. Healthy People 2010, Healthy People 2010 operational definition. Available at: ftp://ftp.cdc.gov/pub/health_statistics/nchs/ Rosenfield A. Outcomes of care in birth centers. The datasets/data2010/focusarea16/O1609a.pdf. Retrieved September National Birth Center Study. N Engl J Med 1989;321: 14, 2012. 1804–11. 4. Clark EA, Silver RM. Long-term maternal morbidity associated 21. Davis LG, Riedmann GL, Sapiro M, Minogue JP, Kazer RR. with repeat cesarean delivery. Am J Obstet Gynecol 2011;205: Cesarean section rates in low-risk private patients managed by S2–10. certified nurse-midwives and obstetricians. J Nurse Midwifery 1994;39:91–7. 5. Berghella V, Blackwell SC, Ramin SM, Sibai BM, Saade GR. Use and misuse of the term ‘elective’ in obstetrics. Obstet 22. Zhang J, Landy HJ, Branch W, Burkman R, Haberman S, Gynecol 2011;117:372–6. Gregory KD, et al. Contemporary patterns of spontaneous labor with normal neonatal outcomes. Obstet Gynecol 2010; 6. Torloni MR, Betran AP, Souza JP, Widmer M, Allen T, 116:1281–7. Gulmezoglu M, et al. Classifications for cesarean section: a sys- tematic review. PLoS One 2011;6:e14566. 23. Anim-Somuah M, Smyth RM, Jones L. Epidural versus non- epidural or no analgesia in labour. The Cochrane Database of 7. Robson MS. Can we reduce the caesarean section rate? Best Systematic Reviews 2011, Issue 12. Art. No.: CD000331. DOI: Pract Res Clin Obstet Gynaecol 2001;15:179–94. 10.1002/14651858.CD000331.pub3. 8. Brennan DJ, Murphy M, Robson MS, O’Herlihy C. The sin- 24. Sharma SK, McIntire DD, Wiley J, Leveno KJ. Labor anal- gleton, cephalic, nulliparous woman after 36 weeks of gestation. gesia and cesarean delivery: an individual patient meta- Obstet Gynecol 2011;117:273–9. analysis of nulliparous women. Anesthesiology 2004;100: 9. Brennan DJ, Robson MS, Murphy M, O’Herlihy C. Comparative 142–8. analysis of international cesarean delivery rates using 10-group 25. Wassen MM, Zuijlen J, Roumen FJ, Smits LJ, Marcus MA, classification identifies significant variation in spontaneous labor. Nijhuis JG. Early versus late epidural analgesia and risk of Am J Obstet Gynecol 2009;201:308.e1–8. instrumental delivery in nulliparous women: a systematic10. Induction of labor. Practice Bulletin No. 107. American Col- review. BJOG 2011;118:655–61. lege of Obstetricians and Gynecologists. Obstet Gynecol 26. Gei AF, Belfort MA. Forceps-assisted vaginal delivery. Obstet 2009;114:386–97. Gynecol Clin North Am 1999;26:345–70.11. Simon CE, Grobman WA. When has an induction failed? 27. Demissie K, Rhoads GG, Smulian JC, Balasubramanian BA, Obstet Gynecol 2005;105:705–9. Gandhi K, Joseph KS, et al. Operative vaginal delivery and12. Harper LM, Caughey AB, Odibo AO, Roehl KA, Zhao Q. Nor- neonatal and infant adverse outcomes: population based retro- mal progress of induced labor. Obstet Gynecol 2012;119:1113–8. spective analysis. BMJ 2004;329:24–9.13. Rouse DJ, Weiner SJ, Bloom SL, Varner MW, Spong CY, 28. Gardella C, Taylor M, Benedetti T, Hitti J, Critchlow C. The Ramin SM, et al; Eunice Kennedy Shriver National Institute of effect of sequential use of vacuum and forceps for assisted vag- Child Health and Human Development (NICHD) Maternal- inal delivery on neonatal and maternal outcomes. Am J Obstet Fetal Medicine Units Network (MFMU). Failed labor induc- Gynecol 2001;85:896–902. tion: toward an objective diagnosis. Obstet Gynecol 2011; 29. Wesley BD, van den Berg BJ, Reece EA. The effect of forceps 117:267–72. delivery on cognitive development. Am J Obstet Gynecol 1993;14. Macones GA, Hankins GD, Spong CY, Hauth J, Moore T. The 169:1091–5. 2008 National Institute of Child Health and Human Develop- 30. Seidman DS, Laor A, Gale R, Stevenson DK, Mashiach S, ment workshop report on electronic fetal monitoring: update Danon YL. Long-term effects of vacuum and forceps deliveries. on definitions, interpretation, and research guidelines. Obstet Lancet 1991;337:1583–5. Gynecol 2008;112:661–6. 31. Martin JA, Hamilton BE, Sutton PD, Ventura SJ, Menacker F,15. Heimstad R, Skogvoll E, Mattsson LA, Johansen OJ, Eik-New SH, Munson ML. Births: final data for 2002. Natl Vital Stat Rep Salvesen KA. Induction of labor or serial antenatal fetal monitor- 2003;52:1–113. ing in postterm pregnancy. Obstet Gynecol 2007;109:609–17. 32. Murphy M, Hull PM. Choosing cesarean: a natural birth plan.16. A clinical trial of induction of labor versus expectant Amherst (NY): Prometheus Books; 2012. management in postterm pregnancy. The National Institute of Child Health and Human Development Network of 33. Klasko SK, Cummings RV, Balducci J, DeFulvio JD, Reed JF Maternal-Fetal Medicine Units. Am J Obstet Gynecol 3rd. The impact of mandated in-hospital coverage on primary 1994;170:716–23. cesarean delivery rates in a large nonuniversity teaching hospi- tal. Am J Obstet Gynecol 1995;172:637–42.17. Hannah ME, Hannah WJ, Hellmann J, Hewson S, Milner R, Willan A. Induction of labor as compared with serial antenatal 34. Spetz J, Smith MW, Ennis SF. Physician incentives and the monitoring in post-term pregnancy. The Canadian Multicen- timing of cesarean sections: evidence from California. Med ter Postterm Pregnancy Trial Group. N Engl J Med 1992;326: Care 2001;39:536–50. 1587–92. 35. Barber EL, Lundsberg LS, Belanger K, Pettker CM, Funai EF,18. Rouse DJ, Weiner SJ, Bloom SL, Varner MW, Spong CY, Illuzzi JL. Indications contributing to the increasing cesarean Ramin SM, et al. Second-stage labor duration in nulliparous delivery rate. Obstet Gynecol 2011;118:29–38.1192 Spong et al Preventing the First Cesarean Delivery OBSTETRICS & GYNECOLOGY
  • 13. 36. Bailit JL, Love TE, Mercer B. Rising cesarean rates: are patients 38. Vergani P, Ornaghi S, Pozzi I, Beretta P, Russo FM, Follesa I, sicker? Am J Obstet Gynecol 2004;191:800–3. Ghidini A. Placenta previa: distance to internal os and mode of37. Pang MW, Leung TN, Lau TK, Hang Chung TK. Impact of delivery. Am J Obstet Gynecol 2009;201:266.e1–5. first childbirth on changes in women’s preference for mode of 39. Management of intrapartum fetal heart rate tracings. Practice delivery: follow-up of a longitudinal observational study. Birth Bulletin No. 116. American College of Obstetricians and 2008;35:121–8. Gynecologists. Obstet Gynecol 2010;116:1232–40.VOL. 120, NO. 5, NOVEMBER 2012 Spong et al Preventing the First Cesarean Delivery 1193