Which of the Following Is Not a Statement From the Consensus Statement You Read?

Abstruse: In 2011, i in three women who gave birth in the U.s. did so past cesarean delivery. Cesarean birth can be life-saving for the fetus, the female parent, or both in certain cases. Nevertheless, the rapid increase in cesarean birth rates from 1996 to 2011 without clear evidence of concomitant decreases in maternal or neonatal morbidity or mortality raises meaning concern that cesarean delivery is overused. Variation in the rates of nulliparous, term, singleton, vertex cesarean births also indicates that clinical practice patterns affect the number of cesarean births performed. The most common indications for primary cesarean delivery include, in guild of frequency, labor dystocia, aberrant or indeterminate (formerly, nonreassuring) fetal heart rate tracing, fetal malpresentation, multiple gestation, and suspected fetal macrosomia. Safety reduction of the rate of primary cesarean deliveries will crave different approaches for each of these, as well as other, indications. For case, information technology may be necessary to revisit the definition of labor dystocia considering contempo information show that contemporary labor progresses at a rate substantially slower than what was historically taught. Additionally, improved and standardized fetal eye rate interpretation and direction may take an effect. Increasing women'southward admission to nonmedical interventions during labor, such as continuous labor and commitment support, also has been shown to reduce cesarean nativity rates. External cephalic version for breech presentation and a trial of labor for women with twin gestations when the kickoff twin is in cephalic presentation are other of several examples of interventions that can contribute to the safe lowering of the primary cesarean delivery rate.

Background

In 2011, one in three women who gave birth in the U.s. did then by cesarean delivery ane. Even though the rates of principal and total cesarean delivery accept plateaued recently, there was a rapid increase in cesarean rates from 1996 to 2011 Figure 1. Although cesarean commitment can be life-saving for the fetus, the mother, or both in certain cases, the rapid increase in the rate of cesarean births without evidence of concomitant decreases in maternal or neonatal morbidity or bloodshed raises pregnant concern that cesarean delivery is overused two. Therefore, information technology is important for wellness care providers to empathise the brusque-term and long-term tradeoffs between cesarean and vaginal delivery, likewise as the safe and appropriate opportunities to foreclose overuse of cesarean commitment, particularly main cesarean delivery.

Balancing Risks and Benefits

Childbirth past its very nature carries potential risks for the woman and her baby, regardless of the road of delivery. The National Institutes of Health has commissioned evidence-based reports over recent years to examine the risks and benefits of cesarean and vaginal delivery 3 Table 1. For certain clinical conditions—such equally placenta previa or uterine rupture—cesarean delivery is firmly established every bit the safest route of delivery. However, for nigh pregnancies, which are low-risk, cesarean delivery appears to pose greater adventure of maternal morbidity and mortality than vaginal commitment 4 Tabular array 1.

It is difficult to isolate the morbidity caused specifically by route of delivery. For example, in i of the few randomized trials of approach to delivery, women with a breech presentation were randomized to undergo planned cesarean delivery or planned vaginal delivery, although there was crossover in both treatment arms 5. In this study, at three-month follow-upwardly, women were more likely to have urinary, but not fecal, incontinence if they had been randomized to the planned vaginal commitment group. However, this difference was no longer meaning at 2-year follow-up half-dozen. Because of the size of this randomized trial, information technology was not powered to wait at other measures of maternal morbidity.

A large population-based study from Canada found that the run a risk of severe maternal morbidities—defined as hemorrhage that requires hysterectomy or transfusion, uterine rupture, anesthetic complications, stupor, cardiac arrest, acute renal failure, assisted ventilation, venous thromboembolism, major infection, or in hospital wound disruption or hematoma—was increased threefold for cesarean delivery equally compared with vaginal commitment (ii.vii% versus 0.nine%, respectively) 7. There also are concerns regarding the long-term risks associated with cesarean commitment, particularly those associated with subsequent pregnancies. The incidence of placental abnormalities, such as placenta previa, in futurity pregnancies increases with each subsequent cesarean delivery, from 1% with one prior cesarean delivery to almost iii% with three or more prior cesarean deliveries. In improver, an increasing number of prior cesareans is associated with the morbidity of placental previa: afterwards 3 cesarean deliveries, the risk that a placenta previa will be complicated by placenta accreta is nearly 40% 8. This combination of complications not only significantly increases maternal morbidity but also increases the gamble of adverse neonatal outcomes, such as neonatal intensive intendance unit admission and perinatal death 3 nine 10. Thus, although the initial cesarean delivery is associated with some increases in morbidity and mortality, the downstream effects are even greater because of the risks from repeat cesareans in future pregnancies 11.

Indications for Chief Cesarean

At that place is corking regional variation past state in the rate of full cesarean delivery beyond the U.s., ranging from a low of 23% to a loftier of almost 40% Figure 2. Variation in the rates of nulliparous term singleton vertex cesarean births indicates that clinical practice patterns affect the number of cesarean births performed. There also is substantial infirmary-level variation. Studies have shown a 10-fold variation in the cesarean delivery rate across hospitals in the United States, from 7.one% to 69.9%, and a fifteen-fold variation among depression-adventure women, from two.4% to 36.5% 12. Studies that take evaluated the office of maternal characteristics, such as age, weight, and ethnicity, have consistently found these factors do non business relationship fully for the temporal increase in the cesarean commitment rate or its regional variations thirteen 14 15. These findings suggest that other potentially modifiable factors, such as patient preferences and practice variation among hospitals, systems, and health intendance providers, likely contribute to the escalating cesarean delivery rates.

In gild to understand the degree to which cesarean deliveries may exist preventable, it is important to know why cesareans are performed. In a 2011 population-based report, the nearly mutual indications for primary cesarean commitment included, in club of frequency, labor dystocia, abnormal or indeterminate (formerly, nonreassuring) fetal centre rate tracing, fetal malpresentation, multiple gestation, and suspected fetal macrosomia Figure 3 16. Abort of labor and abnormal or indeterminate fetal middle rate tracing accounted for more than than i half of all main cesarean deliveries in the written report population. Prophylactic reduction of the rate of master cesarean deliveries will require dissimilar approaches for each of these indications. For example, it may be necessary to revisit the definition of labor dystocia considering recent data testify that gimmicky labor progresses at a charge per unit substantially slower than what has been historically taught. Improved and standardized fetal heart charge per unit interpretation and management also may have an effect. Increasing women's access to nonmedical interventions during labor, such equally continuous labor support, also has been shown to reduce cesarean birth rates. External cephalic version for breech presentation and a trial of labor for women with twin gestations when the first twin is in cephalic presentation also tin can contribute to the rubber lowering of the primary cesarean commitment rate.

Clinical Management Questions and Answers

What is the appropriate definition of abnormally progressing offset-stage labor?

Definition of Aberrant Showtime-Stage Labor

The first phase of labor has been historically divided into the latent phase and the active phase based on the work past Friedman in the 1950s and across. The latent phase of labor is defined equally beginning with maternal perception of regular contractions 17. On the basis of the 95th percentile threshold, historically, the latent phase has been defined as prolonged when it exceeds twenty hours in nulliparous women and 14 hours in multiparous women 18. The active phase of labor has been defined as the indicate at which the charge per unit of alter of cervical dilation significantly increases.

Agile phase labor abnormalities can be categorized either as protraction disorders (slower progress than normal) or abort disorders (complete abeyance of progress). Based on Friedman's piece of work, the traditional definition of a protracted active phase (based on the 95th percentile) has been cervical dilatation in the active stage of less than 1.2 cm/h for nulliparous women and less than 1.5 cm/h for multiparous women 19. Active stage arrest traditionally has been defined as the absence of cervical change for two hours or more in the presence of acceptable uterine contractions and cervical dilation of at least 4 cm.

Even so, more than recent data from the Consortium on Safe Labor take been used to revise the definition of contemporary normal labor progress twenty. In this retrospective study conducted at xix U.Southward. hospitals, the duration of labor was analyzed in 62,415 parturient women, each of whom delivered a singleton vertex fetus vaginally and had a normal perinatal result. In this study, the 95th percentile rate of active phase dilation was substantially slower than the standard rate derived from Friedman'southward work, varying from 0.5 cm/h to 0.seven cm/h for nulliparous women and from 0.5 cm/h to 1.3 cm/h for multiparous women (the ranges reflect that at more advanced dilation, labor proceeded more quickly) Tabular array 2.

The Consortium on Condom Labor information highlight two important features of contemporary labor progress Effigy 4. First, from 4–6 cm, nulliparous and multiparous women dilated at essentially the same charge per unit, and more slowly than historically described. Across six cm, multiparous women dilated more than rapidly. 2d, the maximal slope in the rate of change of cervical dilation over fourth dimension (ie, the active phase) often did not commencement until at least 6 cm. The Consortium on Safe Labor data practice not directly address an optimal duration for the diagnosis of agile phase protraction or labor abort, but do suggest that neither should exist diagnosed before half dozen cm of dilation. Because they are gimmicky and robust, it seems that the Consortium on Rubber Labor data, rather than the standards proposed by Friedman, should inform bear witness-based labor management.

How should abnormally progressing first-stage labor be managed?

Management of Abnormal First-Stage Labor

Although labor management strategies predicated on the recent Consortium on Condom Labor information have not been assessed yet, some insight into how management of aberrant start-stage labor might be optimized tin exist deduced from prior studies.

The definitions of a prolonged latent phase are still based on data from Friedman and modern investigators take not particularly focused on the latent stage of labor. Most women with a prolonged latent phase ultimately will enter the active stage with expectant management. With few exceptions, the remainder either will terminate contracting or, with amniotomy or oxytocin (or both), achieve the active phase 18. Thus, a prolonged latent stage (eg, greater than 20 hours in nulliparous women and greater than 14 hours in multiparous women) should not be an indication for cesarean delivery Tabular array 3.

When the get-go stage of labor is protracted or arrested, oxytocin is commonly recommended. Several studies have evaluated the optimal duration of oxytocin augmentation in the confront of labor protraction or abort. A prospective study of the progress of labor in 220 nulliparous women and 99 multiparous women who spontaneously entered labor evaluated the benefit of prolonging oxytocin augmentation for an additional 4 hours (for a total of 8 hours) in patients who were dilated at least 3 cm and had unsatisfactory progress (either protraction or arrest) afterwards an initial 4-hour augmentation period 21. The researchers plant that of women who received at least 4 boosted hours of oxytocin, 38% delivered vaginally, and none had neonates with v-minute Apgar scores of less than 6. In nulliparous women, a period of 8 hours of augmentation resulted in an xviii% cesarean commitment rate and no cases of birth injury or asphyxia, whereas if the flow of augmentation had been limited to 4 hours, the cesarean delivery rate would have been twice equally high given the number of women who had not made pregnant progress at 4 hours. Thus, slow but progressive labor in the first stage of labor should not be an indication for cesarean delivery Table iii.

A study of more than than 500 women found that extending the minimum period of oxytocin augmentation for active phase arrest from 2 hours to at least iv hours allowed the majority of women who had non progressed at the 2-hr mark to give birth vaginally without adversely affecting neonatal outcome 22. The researchers divers agile phase labor arrest every bit 1 cm or less of labor progress over 2 hours in women who entered labor spontaneously and were at least 4 cm dilated at the time arrest was diagnosed. The vaginal delivery charge per unit for women who had non progressed despite 2 hours of oxytocin augmentation was 91% for multiparous women and 74% for nulliparous women. For women who had non progressed despite four hours of oxytocin (and in whom oxytocin was connected at the judgment of the health intendance provider), the vaginal delivery rates were 88% in multiparous women and 56% in nulliparous women. Subsequently, the researchers validated these results in a dissimilar accomplice of 501 prospectively managed women 23. An additional study of 1,014 women conducted past different authors demonstrated that using the same criteria in women with spontaneous labor or induced labor would lead to a significantly higher proportion of women achieving vaginal commitment with no increase in neonatal complications 24. Of note, prolonged starting time stage of labor has been associated with an increased risk of chorioamnionitis in the studies listed, but whether this relationship is causal is unclear (ie, evolving chorioamnionitis may predispose to longer labors). Thus, although this relationship needs further elucidation, neither chorioamnionitis nor its elapsing should be an indication for cesarean delivery 25.

Given these data, every bit long as fetal and maternal status are reassuring, cervical dilation of vi cm should exist considered the threshold for the active phase of nearly women in labor Box 1. Thus, before half-dozen cm of dilation is achieved, standards of active phase progress should not be practical Table 3. Farther, cesarean delivery for active phase arrest in the first stage of labor should be reserved for women at or across vi cm of dilation with ruptured membranes who fail to progress despite iv hours of adequate uterine activity, or at least 6 hours of oxytocin administration with inadequate uterine activity and no cervical modify Table 3 22.

Definition of Abort of Labor in the First Stage

Spontaneous labor: More than or equal to 6 cm dilation with membrane rupture and one of the following:

• 4 hours or more of acceptable contractions (eg, more than than 200 Montevideo units)

• 6 hours or more of inadequate contractions and no cervical alter

What is the appropriate definition of aberrant second-stage labor?

The second stage of labor begins when the cervix becomes fully dilated and ends with commitment of the neonate. Parity, delayed pushing, employ of epidural analgesia, maternal body mass index, nascence weight, occiput posterior position, and fetal station at complete dilation all have been shown to affect the length of the second phase of labor 26. Further, it is important to consider not just the mean or median elapsing of the 2d stage of labor but also the 95th percentile duration. In the Consortium on Rubber Labor written report discussed earlier, although the mean and median duration of the second stage differed by 30 minutes, the 95th percentile threshold was approximately one hour longer in women who received epidural analgesia than in those who did non twenty.

Defining what constitutes an appropriate elapsing of the second stage is not straightforward because it involves a consideration of multiple short-term and long-term maternal and neonatal outcomes—some of them competing. Multiple investigators have examined the relationship between the duration of the second stage of labor and agin maternal and neonatal outcomes in an endeavour to define what should constitute a "normal" duration of the second stage. In the era of electronic fetal monitoring, amidst neonates born to nulliparous women, adverse neonatal outcomes generally have not been associated with the duration of the second stage of labor. In a secondary analysis of a multicenter randomized study of fetal pulse oximetry, of four,126 nulliparous women who reached the second stage of labor, none of the following neonatal outcomes was found to be related to the duration of the second stage, which in some cases was 5 hours or more: 5-minute Apgar score of less than 4, umbilical avenue pH less than 7.0, intubation in the commitment room, demand for admission to the neonatal intensive care unit, or neonatal sepsis 27. Similarly, in a secondary analysis of ane,862 women enrolled in an early on versus delayed pushing trial, a longer duration of active pushing was not associated with adverse neonatal outcomes, even in women who pushed for more than 3 hours 28. This besides was found in a large, retrospective cohort study of 15,759 nulliparous women fifty-fifty in a grouping of women whose 2nd stage progressed across four hours 29.

The duration of the 2d stage of labor and its relationship to neonatal outcomes has been less extensively studied in multiparous women. In one retrospective written report of 5,158 multiparous women, when the duration of the 2d stage of labor exceeded 3 hours, the risk of a five-infinitesimal Apgar score of less than 7, access to the neonatal intensive intendance unit, and a composite of neonatal morbidity were all significantly increased 30. A population-based report of 58,113 multiparous women yielded like results when the duration of the 2d stage was greater than two hours 31.

A longer elapsing of the second stage of labor is associated with adverse maternal outcomes, such equally higher rates of puerperal infection, third-degree and fourth-degree perineal lacerations, and postpartum hemorrhage 27. Moreover, for each 60 minutes of the second stage, the chance for spontaneous vaginal delivery decreases progressively. Researchers have found that after a iii-60 minutes or more than second stage of labor, merely one in four nulliparous women 27 and one in 3 multiparous women give birth spontaneously, whereas upward to thirty–fifty% may crave operative delivery to requite birth vaginally in the current second stage of labor threshold surroundings 30.

Thus, the literature supports that for women, longer time in the 2d stage of labor is associated with increased risks of morbidity and a decreasing probability of spontaneous vaginal delivery. However, this risk increase may not be entirely related to the elapsing of the second stage per se, but rather to wellness care provider deportment and interventions in response to information technology (eg, operative delivery and the associated risks of perineal trauma) 32. With advisable monitoring, however, the accented risks of agin fetal and neonatal consequences of increasing 2d stage duration appear to exist, at worst, depression and incremental. For example, in the study of 58,113 multiparous women cited earlier, although the take chances of a 5-minute Apgar score of less than vii and nascence depression was increased when the 2nd stage of labor lasted longer than 2 hours, the absolute risk of these outcomes was low (less than 1.five%) with durations less than 2 hours and was not doubled even with durations greater than five hours. Moreover, the duration of the 2nd stage of labor was unrelated to the risk of neonatal sepsis or major trauma. Thus, a specific absolute maximum length of fourth dimension spent in the 2nd stage of labor beyond which all women should undergo operative delivery has non been identified Table iii. Similar to the outset stage of labor, a prolonged second stage of labor has been associated with an increased risk of chorioamnionitis in the studies listed, but whether this relationship is causal is unclear (ie, evolving chorioamnionitis may predispose to longer labors). Again, neither chorioamnionitis nor its duration should be an indication for cesarean delivery.

How should abnormally progressing second-stage labor exist managed?

Given the available literature, earlier diagnosing arrest of labor in the second stage and if the maternal and fetal conditions permit, at least 2 hours of pushing in multiparous women and at to the lowest degree 3 hours of pushing in nulliparous women should be allowed Table 3. Longer durations may exist appropriate on an individualized footing (eg, with the use of epidural analgesia or with fetal malposition) as long as progress is being documented Table iii. For example, the recent Eunice Kennedy Shriver National Institute of Child Health and Human Development document suggested allowing one additional hour in the setting of an epidural, thus, at to the lowest degree 3 hours in multiparous women and 4 hours in nulliparous women be used to diagnose second-stage arrest, although that certificate did not clarify betwixt pushing fourth dimension or total second stage 33.

What other direction approaches may reduce cesarean deliveries in the second phase of labor?

In addition to greater expectant management of the 2nd stage, 2 other practices could potentially reduce cesarean deliveries in the 2d stage: i) operative vaginal commitment and 2) manual rotation of the fetal occiput for malposition.

Operative Vaginal Delivery

In contrast with the increasing rate of cesarean delivery, the rates of operative vaginal deliveries (via either vacuum or forceps), accept decreased significantly during the past 15 years 34. Yet, comparison of the outcomes of operative vaginal deliveries and unplanned cesarean deliveries shows no departure in serious neonatal morbidity (eg, intracerebral hemorrhage or death). In a large, retrospective cohort written report, the charge per unit of intracranial hemorrhage associated with vacuum extraction did non differ significantly from that associated with either forceps delivery (odds ratio [OR], i.two; 95% confidence interval [CI], 0.7–2.2) or cesarean delivery (OR, 0.9; 95% CI, 0.half-dozen–1.4) 35. In a more recent written report, forceps-assisted vaginal deliveries were associated with a reduced gamble of the combined outcome of seizure, intraventricular hemorrhage, or subdural hemorrhage as compared with either vacuum-assisted vaginal delivery (OR, 0.sixty; 95% CI, 0.40–0.90) or cesarean delivery (OR, 0.68; 95% CI, 0.48–0.97), with no significant difference between vacuum delivery or cesarean delivery 36.

Fewer than 3% of women in whom an operative vaginal delivery has been attempted go on to evangelize past cesarean 37. Although attempts at operative vaginal commitment from a mid-pelvic station (0 and +ane on the -5 to +5 scale) or from an occiput transverse or occiput posterior position with rotation are reasonable in selected cases 38, these procedures require a college level of skill and are more likely to neglect than low (+2 or greater) or outlet (scalp visible at the introitus) operative deliveries. Performing low or outlet procedures in fetuses not believed to exist macrosomic is likely to safely reduce the risk of cesarean delivery in the second stage of labor. Notwithstanding, the number of wellness intendance providers who are fairly trained to perform forceps and vacuum deliveries is decreasing. In one survey, most (55%) resident physicians in preparation did not experience competent to perform a forceps delivery upon completion of residency 39. Thus, grooming resident physicians in the operation of operative vaginal deliveries and using simulation for retraining and ongoing maintenance of practise would likely contribute to a safe lowering of the cesarean delivery rate 40. In sum, operative vaginal delivery in the second stage of labor by experienced and well trained physicians should be considered a safety, acceptable alternative to cesarean delivery. Grooming in, and ongoing maintenance of, practical skills related to operative vaginal delivery should be encouraged Tabular array three.

Manual Rotation of the Fetal Occiput

Occiput posterior and occiput transverse positions are associated with an increase in cesarean commitment and neonatal complications 41 42. Historically, forceps rotation of the fetal occiput from occiput posterior or occiput transverse was mutual practise. Today this procedure, although yet considered a reasonable management approach, has fallen out of favor and is rarely taught in the U.s.a.. An alternative approach is manual rotation of the fetal occiput, which has been associated with a safe reduction in the hazard of cesarean delivery and is supported past the Society of Obstetricians and Gynaecologists of Canada 43 44 45. For instance, in a small prospective trial of 61 women, those who were offered a trial of transmission rotation experienced a lower rate of cesarean delivery (0%) compared with those managed without manual rotation (23%, P=.001) 46. A large, retrospective accomplice study found a similar big reduction in cesarean delivery (9% versus 41%, P< .001) associated with the use of manual rotation 43. Of the 731 women in this written report who underwent manual rotation, none experienced an umbilical cord prolapse. Farther, there was no divergence in either nativity trauma or neonatal acidemia between neonates who had experienced an attempt at manual rotation versus those who had not 43. In society to consider an intervention for a fetal malposition, the proper cess of fetal position must be made. Intrapartum ultrasonography has been used to increase the accurate diagnosis of fetal position when the digital examination results are uncertain 47.

Given these data, which is express for rubber and efficacy, manual rotation of the fetal occiput in the setting of fetal malposition in the 2nd stage of labor is a reasonable intervention to consider before moving to operative vaginal delivery or cesarean delivery. In club to safely prevent cesarean deliveries in the setting of malposition, it is of import to assess the fetal position in the second phase of labor, especially in the setting of abnormal fetal descent Tabular array iii.

Which fetal heart tracings deserve intervention, and what are these interventions?

The second virtually common indication for primary cesarean is an abnormal or indeterminate fetal centre rate tracing Figure 3. Given the known variation in interpretation and direction of fetal heart rate tracings, a standardized approach is a logical potential goal for interventions to safely reduce the cesarean commitment rate.

Category III fetal center charge per unit tracings are abnormal and crave intervention 48. The elements of Category Iii patterns—which include either absent fetal centre charge per unit variability with recurrent late decelerations, recurrent variable decelerations, or bradycardia; or a sinus oidal rhythm—have been associated with abnormal neonatal arterial umbilical cord pH, encephalopathy, and cognitive palsy 49 50 51 52. Intrauterine resuscitative efforts—including maternal repositioning and oxygen supplementation, assessment for hypotension and tachysystole that may exist corrected, and evaluation for other causes, such as umbilical cord prolapse—should be performed expeditiously; however, when such efforts do not quickly resolve the Category Three tracing, delivery as rapidly and as safely possible is indicated. The American Higher of Obstetricians and Gynecologists recommends preparations for imminent delivery in the event that intrauterine resuscitative measures do not meliorate the fetal heart rate pattern 48.

In contrast, Category I fetal eye tracings are normal and practise not require intervention other than on going assessment with continuous or intermittent monitoring, given that patterns can alter over time. Moderate variability and the presence of accelerations, which are features of Category I patterns, have proved to be reliable indicators of normal neonatal umbilical cord arterial pH (7.twenty or greater) 53 54.

Near intrapartum fetal heart rate tracings are Category II fifty 55. Category Two tracings are indeterminate and comprise a various spectrum of fetal center rate patterns that crave evaluation, continued surveillance, initiation of appropriate corrective measures when indicated, and re-evaluation 48. Based on the high rate of first cesarean deliveries performed for the indication of "nonreassuring fetal centre rate" (also known as an "aberrant or indeterminate fetal center rate") and the rarity of Category III patterns, it tin can exist deduced that Category Two tracings probable account for most cesarean deliveries performed for nonreassuring fetal condition 16. Thus, 1 important consideration for health care providers who are making the diagnosis of nonreassuring fetal status with the intent to proceed with cesarean delivery is to ensure that clinically indicated measures have been undertaken to resolve the apropos elements of the Category Ii tracing or provide reassurance of fetal well-being.

Scalp stimulation to elicit a fetal eye rate acceleration is an easily employed tool when the cervix is dilated and can offer clinician reassurance that the fetus is not acidotic. Spontaneous or elicited eye charge per unit accelerations are associated with a normal umbilical cord arterial pH (7.20 or greater) 54 56. Recurrent variable decelerations, thought to be a physiologic response to repetitive compression of the umbilical cord, are non themselves pathologic. However, if frequent and persistent, they can lead to fetal acidemia over time. Conservative measures, such as position change, may improve this pattern. Amnioinfusion with normal saline also has been demonstrated to resolve variable fetal centre rate decelerations 57 58 59 and reduce the incidence of cesarean commitment for a nonreassuring fetal heart charge per unit blueprint 59 60 61. Similarly, other elements of Category II fetal heart rate tracings that may betoken fetal acidemia, such every bit minimal variability or recurrent belatedly decelerations, should be approached with in utero resuscitation 48.

Prolonged fetal heart rate decelerations (which last more than 2 minutes merely less than 10 minutes) oftentimes require intervention. They can occur after rapid cervical change or after hypotension (ie, in the setting of regional analgesia). Prolonged decelerations also may be a sign of complications, such every bit abruptio placentae, umbilical cord prolapse, or uterine rupture; because of their potential morbidity, these complications should be considered in the differential diagnosis to allow for appropriate evaluation and intervention 62 63 64. Uterine tachysystole, divers equally more than five contractions in 10 minutes averaged over 30 minutes, can occur spontaneously or considering of uterotonic agents (ie, oxytocin or prostaglandins) and can be associated with fetal heart rate changes, such as prolonged or late decelerations. Reduction or abeyance of the contractile agent or administration of a uterine relaxant, such equally a beta-mimetic agent, can resolve uterine tachysystole and ameliorate the fetal heart charge per unit tracing 65. In contrast, at that place are no current data to support interventions specifically for decelerations with "singular features" (such as shoulders, slow return to baseline, or variability just inside the deceleration) because they have not been associated with fetal acidemia 49 66.

There is not consequent evidence that ST-segment analysis and fetal pulse oximetry either amend outcomes or reduce cesarean delivery rates 67 68. Despite the evidence that fetal scalp sampling reduces the chance of cesarean delivery 69 seventy and the poor ability of electronic fetal heart rate monitoring patterns to predict pH, intrapartum fetal scalp sampling has fallen out of favor in the U.s.a.. This predominantly is due to its invasive nature, the narrow clinical presentations for which it might exist helpful, and the need for regulatory measures to maintain bedside testing availability. Currently, this testing is not performed in most U.S. centers and a fetal claret sampling "kit" that is approved by the U.S. Nutrient and Drug Administration is non currently manufactured.

The unnecessary operation of cesarean deliveries for abnormal or indeterminate fetal centre rate tracings tin be attributed to limited knowledge about the ability of the patterns to predict neonatal outcomes and the lack of rigorous science to guide clinical response to the patterns 55 71. Supplemental oxygen 72, intravenous fluid bolus 73, and tocolytic agents 74 are routine components of intrauterine resuscitation 75 that have extremely express data for effectiveness or safety. Operation of these interventions without a subsequent alter in fetal eye rate pattern is not necessarily an indication for cesarean delivery. Medication exposure, regional analgesia, rapid labor progress, cervical examination, infection, maternal hypotension, and maternal fever all can affect the fetal heart charge per unit design 48. Attending to such factors volition optimize clinical decision making regarding the management of abnormal or indeterminate fetal heart rate patterns and the demand for cesarean commitment. Specifically, amnioinfusion for repetitive variable fetal heart rate decelerations may safely reduce the rate of cesarean delivery Tabular array iii. Scalp stimulation can be used as a means of assessing fetal acid–base status when abnormal or indeterminate (formerly, nonreassuring) fetal heart patterns (eg, minimal variability) are nowadays and is a rubber culling to cesarean delivery in this setting Table iii.

What is the issue of induction of labor on cesarean delivery?

The use of induction of labor has increased in the United States concurrently with the increase in the cesarean delivery rate, from ix.v% of births in 1990 to 23.1% of births in 2008 76 77. Because women who undergo consecration of labor have college rates of cesarean commitment than those who experience spontaneous labor, it has been widely assumed that induction of labor itself increases the risk of cesarean commitment. However, this supposition is predicated on a faulty comparing of women who are induced versus women in spontaneous labor 78. Studies that compare induction of labor to its actual culling, expectant direction awaiting spontaneous labor, accept found either no difference or a decreased risk of cesarean delivery amid women who are induced 79 80 81 82. This appears to be truthful fifty-fifty for women with an unfavorable neck 83.

Available randomized trial data comparison induction of labor versus expectant management reinforce the more than recent observational information. For case, a meta-assay of prospective randomized controlled trials conducted at less than 42 0/7 weeks of gestation, found that women who underwent induction of labor had a lower charge per unit of cesarean commitment compared with those who received expectant management 84. In add-on, a meta-analysis of 3 older, pocket-sized studies of induction of labor before 41 0/vii weeks of gestation also demonstrated a statistically pregnant reduction in the rate of cesarean delivery 85. Additionally, increases in stillbirth, neonatal, and infant death take been associated with gestations at 41 0/vii weeks and beyond 86 87. In a 2012 Cochrane meta-analysis, induction of labor at 41 0/vii weeks of gestation and beyond was associated with a reduction in perinatal mortality when compared with expectant management 85. Therefore, before 41 0/seven weeks of gestation, consecration of labor generally should be performed based on maternal and fetal medical indications. Inductions at 41 0/7 weeks of gestation and beyond should exist performed to reduce the risk of cesarean delivery and the take chances of perinatal morbidity and mortality Table 3.

Once a decision has been made to proceed with a labor consecration, variations in the management of labor induction likely affect rates of cesarean delivery, peculiarly the use of cervical ripening agents for the unfavorable neck and the lack of a standard definition of what constitutes prolonged elapsing of the latent stage (a failed consecration). Numerous studies take found that the use of cervical ripening methods—such equally misoprostol, dinoprostone, prostaglandin E₂ gel, Foley bulbs, and laminaria tents—atomic number 82 to lower rates of cesarean delivery than induction of labor without cervical ripening 69 88. The benefit is and then widely accustomed that recent studies do not include a placebo or nonintervention group, but rather compare one cervical ripening method with another 89. There also are information to support the use of more than one of these methods sequentially or in combination, such as misoprostol and a Foley bulb, to facilitate cervical ripening 90. Thus, cervical ripening methods should be used when labor is induced in women with an unfavorable cervix Table three.

In the setting of consecration of labor, nonintervention in the latent phase when the fetal middle tracing is reassuring and maternal and fetal statuses are stable seems to reduce the risk of cesarean delivery. Contempo information point that the latent stage of labor is longer in induced labor compared with spontaneous labor 91. Furthermore, at least three studies back up that a substantial proportion of women undergoing consecration who remain in the latent phase of labor for 12–18 hours with oxytocin administration and ruptured membranes will give birth vaginally if induction is continued 92 93 94. In one study, 17% of women were nonetheless in the latent phase of labor after 12 hours, and v% remained in the latent phase beyond xviii hours 93. In some other study, of those women who were in the latent phase for longer than 12 hours and achieved active phase of labor, the majority (lx%) gave birth vaginally 94. Membrane rupture and oxytocin administration, except in rare circumstances, should be considered prerequisites to any definition of failed labor induction, and experts take proposed waiting at least 24 hours in the setting of oxytocin and ruptured membranes before declaring an consecration failed 33.

Therefore, if the maternal and fetal status allow, cesarean deliveries for failed induction of labor in the latent phase can be avoided past allowing longer durations of the latent phase (upwards to 24 hours or longer) and requiring that oxytocin be administered for at least 12–xviii hours after membrane rupture before deeming the induction a failure Table iii.

What are the other indications for primary cesarean delivery? What alternative management strategies tin be used for the safe prevention of cesarean delivery in these cases?

Although labor arrest and abnormal or indeterminate fetal eye rate tracing are the most common indications for primary cesarean delivery, less common indications—such equally fetal malpresentation, suspected macrosomia, multiple gestation, and maternal infection (eg, herpes simplex virus)—business relationship for tens of thousands of cesarean deliveries in the United States annually. Rubber prevention of master cesarean deliveries will crave different approaches for each of these indications.

Fetal Malpresentation

Breech presentation at 37 weeks of gestation and beyond is estimated to complicate three.viii% of pregnancies, and more than than 85% of pregnant women with a persistent breech presentation are delivered by cesarean 95. In 1 recent study, the rate of attempted external cephalic version was 46% and decreased during the report flow 96. Thus, external cephalic version for fetal malpresentation is likely underutilized, specially when considering that nigh patients with a successful external cephalic version will give nascence vaginally 96. Obstetricians should offering and perform external cephalic version whenever possible 97. Furthermore, when an external cephalic version is planned, there is evidence that success may be enhanced by regional analgesia 98. Fetal presentation should be assessed and documented showtime at 36 0/7 weeks of gestation to allow for external cephalic version to be offered Table 3. Before a vaginal breech delivery is planned, women should be informed that the take a chance of perinatal or neonatal bloodshed or short-term serious neonatal morbidity may be higher than if a cesarean delivery is planned, and the patient's informed consent should exist documented.

Suspected Fetal Macrosomia

Suspected fetal macrosomia is not an indication for delivery and rarely is an indication for cesarean delivery. To avoid potential birth trauma, the College recommends that cesarean delivery exist express to estimated fetal weights of at least 5,000 g in women without diabetes and at least iv,500 yard in women with diabetes Table 3 99. This recommendation is based on estimations of the number needed to treat from a study that modeled the potential risks and benefits from a scheduled, nonmedically indicated cesarean commitment for suspected fetal macrosomia, including shoulder dystocias and permanent brachial plexus injuries 100. The prevalence of birth weight of v,000 1000 or more is rare, and patients should be counseled that estimates of fetal weight, particularly tardily in gestation, are imprecise Tabular array 3. Even when these thresholds are non reached, screening ultrasonography performed late in pregnancy has been associated with the unintended issue of increased cesarean commitment with no evidence of neonatal benefit 101. Thus, ultrasonography for estimated fetal weight in the 3rd trimester should be used sparingly and with clear indications.

Excessive Maternal Weight Proceeds

A large proportion of women in the United States proceeds more than weight during pregnancy than is recommended by the Institute of Medicine (IOM). Observational evidence suggests that women who gain more weight than recommended by the IOM guidelines have an increased take chances of cesarean delivery and other adverse outcomes 15 102 103. In a contempo Committee Opinion, the College recommends that information technology is "important to discuss appropriate weight gain, nutrition, and practice at the initial visit and periodically throughout the pregnancy" 104. Although pregnancy weight-management interventions continue to be developed and have yet to interpret into reduced rates of cesarean commitment or morbidity, the available observational data back up that women should be counseled about the IOM maternal weight guidelines in an attempt to avoid excessive weight proceeds Table 3.

Twin Gestation

The rate of cesarean deliveries among women with twin gestations increased from 53% in 1995 to 75% in 2008 105. Fifty-fifty among vertex-presenting twins, in that location was an increase from 45% to 68% 105. Perinatal outcomes for twin gestations in which the first twin is in cephalic presentation are non improved by cesarean commitment. Thus, women with either cephalic/cephalic-presenting twins or cephalic/noncephalic-presenting twins should be counseled to try vaginal delivery Table 3 106. In order to ensure safe vaginal delivery of twins, it is important to train residents to perform twin deliveries and to maintain experience with twin vaginal deliveries among practicing obstetric care providers.

Canker Simplex Virus

In women with a history of herpes simplex virus, the assistants of acyclovir for viral suppression is an important strategy to prevent genital herpetic outbreaks requiring cesarean delivery and asymptomatic viral shedding 107 108. Given the favorable do good-risk profile for the administration of maternal acyclovir, efforts should be fabricated to ensure that women with a history of genital canker, even in the absence of an outbreak in the current pregnancy, are offered oral suppressive therapy within three–4 weeks of anticipated delivery 109 and at the latest, at or beyond 36 weeks of gestation 110. Cesarean commitment is not recommended for women with a history of herpes simplex virus infection only no active genital affliction during labor 110.

Continuous Labor and Delivery Back up

Published data indicate that one of the most effective tools to improve labor and commitment outcomes is the continuous presence of back up personnel, such as a doula. A Cochrane meta-analysis of 12 trials and more than 15,000 women demonstrated that the presence of continuous i-on-i support during labor and delivery was associated with improved patient satisfaction and a statistically significant reduction in the rate of cesarean commitment 111. Given that there are no associated measurable harms, this resource is probably underutilized.

What organizational actions are necessary for the primary cesarean delivery rate to safely decline?

A number of approaches are needed to reduce the chief cesarean delivery rate, which in plough would lower the repeat cesarean commitment rate. Although national and regional organizations can take the atomic number 82 in setting the calendar regarding the safe prevention of master cesarean delivery, such an agenda will need to be prioritized at the level of practices, hospitals, health care systems, and, of course, patients.

Irresolute the local civilisation and attitudes of obstetric care providers regarding the problems involved in cesarean delivery reduction likewise will exist challenging. Several studies have demonstrated the feasibility of using systemic interventions to reduce the rate of cesarean delivery across indications and beyond community and academic settings. A 2007 review found that the cesarean delivery rate was reduced by 13% when audit and feedback were used exclusively only decreased by 27% when audit and feedback were used every bit part of a multifaceted intervention, which involved second opinions and civilisation alter 112. Systemic interventions, therefore, provide an important strategic opportunity for reducing cesarean delivery rates. Notwithstanding, the specific interventional approaches have not been studied in large, prospective trials, thus specific recommendations cannot be fabricated.

A necessary component of civilization change will be tort reform because the practice surround is extremely vulnerable to external medico-legal pressures. Studies have demonstrated associations between cesarean delivery rates and malpractice premiums and state-level tort regulations, such as caps on damages 113 114. A wide range of bear witness-based approaches will be necessary—including changes in individual clinician practice patterns, development of clinical direction guidelines from a wide range of organizations, implementation of systemic approaches at the organizational level and regional level, and tort reform—to ensure that unnecessary cesarean deliveries are reduced. In addition, individuals, organizations, and governing bodies should work to ensure that enquiry is conducted to provide a better cognition base to guide decisions regarding cesarean delivery and to encourage policy changes that safely lower the rate of master cesarean delivery Table 3.

Society for Maternal-Fetal Medicine Grading System: Grading of Recommendations Assessment, Development, and Evaluation (Grade) Recommendations

Obstetric Care Consensus documents will use Order for Maternal-Fetal Medicine’s grading arroyo: http://world wide web.ajog.org/article/S0002-9378%2813%2900744-8/fulltext. Recommendations are classified as either strong (Grade 1) or weak (Grade 2), and quality of testify is classified as high (Course A), moderate (Grade B), and low (Grade C)*. Thus, the recommendations can exist 1 of the following 6 possibilities: 1A, 1B, 1C, 2A, 2B, 2C.

Grade of Recommendation	Clarity of Risk and Benefit	Quality of Supporting Bear witness	Implications
1A. Strong recommendation, high quality prove	Benefits conspicuously outweigh risk and burdens, or vice versa.	Consistent evidence from well performed randomized controlled trials or over-whelming prove of some other class. Further inquiry is unlikely to change confidence in the gauge of do good and take chances.	Strong recommendations, can utilize to most patients in almost circumstances without reservation. Clinicians should follow a strong recommendation unless a clear and compelling rationale for an alternative approach is present.
1B. Potent recommendation, moderate quality testify	Benefits conspicuously outweigh risk and burdens, or vice versa.	Show from randomized controlled trials with important limitations (inconsistent results, methodologic flaws, indirect or imprecise), or very strong prove of another research design. Further research (if performed) is probable to take an impact on confidence in the guess of benefit and risk and may change the estimate.	Strong recommendation, and applies to most patients. Clinicians should follow a strong recommendation unless a clear and compelling rationale for an culling approach is present.
1C. Potent recommendation, low quality testify	Benefits appear to outweigh risk and burdens, or vice versa.	Evidence from observational studies, unsystematic clinical experience, or from randomized controlled trials with serious flaws. Any estimate of outcome is uncertain.	Strong recommendation, and applies to almost patients. Some of the evidence base supporting the recommendation is, however, of depression quality.
2A. Weak recommendation, high quality show	Benefits closely balanced with risks and burdens.	Consistent evidence from well-performed randomized controlled trials or over-whelming evidence of another course. Further research is unlikely to change confidence in the gauge of do good and risk.	Weak recommendation, best activity may differ depending on circumstances or patients or societal values.
2B. Weak recommendation, moderate quality evidence	Benefits closely counterbalanced with risks and burdens; some uncertainty in the estimates of benefits, risks, and burdens.	Prove from randomized controlled trials with important limitations (inconsistent results, methodologic flaws, indirect or imprecise), or very stiff evidence of some other research pattern. Further enquiry (if performed) is likely to have an effect on confidence in the judge of do good and adventure and may alter the estimate.	Weak recommendation, alternative approaches probable to be amend for some patients nether some circumstances.
2C. Weak recommendation, low quality evidence	Dubiety in the estimates of benefits, risks, and burdens; benefits may exist closely balanced with risks and burdens.	Evidence from observational studies, unsystematic clinical experience, or from randomized controlled trials with serious flaws. Any approximate of result is uncertain.	Very weak recommendation, other alternatives may be equally reasonable
Best practice	Recommendation in which either (i) there is enormous amount of indirect bear witness that conspicuously justifies potent recommendation (direct testify would be challenging, and inefficient use of time and resource, to join and carefully summarize), or (2) recommendation to contrary would be unethical.

Modified from Grading guide. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2013. Available at: http://www.uptodate.com/home/grading-guide. Retrieved October nine, 2013.

*Guyatt GH, Oxman Advertizement, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, et al. GRADE: an emerging consensus on rating quality of prove and strength of recommendations.GRADE Working Group. BMJ 2008;336:924–six.

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Source: https://www.acog.org/clinical/clinical-guidance/obstetric-care-consensus/articles/2014/03/safe-prevention-of-the-primary-cesarean-delivery

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