Cesarean delivery is defined as the delivery of a fetus through surgical incisions made through the abdominal wall (laparotomy) and the uterine wall (hysterotomy). In 2014, 32.2% of women who gave birth in the United States did so by cesarean delivery. [1] The rapid increase in cesarean birth rates from 1996 to 2014 without clear evidence of concomitant decreases in maternal or neonatal morbidity or mortality raises significant concern that cesarean delivery is overused. The most common indications for primary cesarean delivery include labor dystocia, abnormal or indeterminate fetal heart rate tracing, fetal malpresentation, multiple gestation, and suspected fetal macrosomia. Safe reduction of the primary cesarean delivery rate will require different approaches for these indications, as well as others. Increasing women's access to nonmedical interventions during labor has also 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 are examples of interventions that can help to safely lower the primary cesarean delivery rate. [2] A practice bulletin from the American College of Obstetricians and Gynecologists (ACOG) recommends that all eligible women with breech presentations who are near term should be offered external cephalic version (ECV) to decrease the overall rate of cesarean delivery. [3, 4] ACOG/SMFM guidelines for prevention of primary cesarean deliveryThe American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM) released joint guidelines for the safe prevention of primary cesarean delivery. These include the following [5, 6] :
IndicationsCesarean deliveries were initially performed to separate the mother and the fetus in an attempt to save the fetus of a moribund patient. They subsequently developed to resolve maternal or fetal complications not amenable to vaginal delivery, either for mechanical limitations or to temporize delivery for maternal or fetal benefit. The leading indications for cesarean delivery (85%) are previous cesarean delivery, breech presentation, dystocia, and fetal distress. [7] Maternal indications for cesarean delivery include the following:
Fetal indications for cesarean delivery include the following:
Indications for cesarean delivery that benefit the mother and the fetus include the following:
There are few contraindications to performing a cesarean delivery. In some circumstances, a cesarean delivery should be avoided, such as the following:
Controversy exists regarding elective cesarean delivery on maternal request (CDMR). The 2013 American College of Obstetricians and Gynecologists (ACOG) Committee on Obstetric Practice [9] and 2006 National Institutes of Health (NIH) consensus committee [10] determined that the evidence supporting this concept was not conclusive and that more research is needed. Both committees provided the following recommendations regarding CDMR [9, 10] :
The NIH consensus panel on CDMR also noted the following [10] :
Guidelines recommend a minimum preoperative fasting time of at least 2 hours from clear liquids, 6 hours from a light meal, and 8 hours from a regular meal. [11] However, patients are usually asked not to eat anything for 12 hours prior to the procedure. [12] The following are also included in preoperative management:
Laboratory testing The following laboratory studies may be obtained prior to cesarean delivery:
Imaging studies In labor and delivery, document fetal position and estimated fetal weight. Although ultrasonography is commonly used to estimate fetal weight, a prospective study reported the sensitivity of clinical and ultrasonographic prediction of macrosomia, respectively, as 68% and 58%. [14] The technique for cesarean delivery includes the following:
See the list below:
See the list below:
The graph below depicts cesarean delivery rates in the US (1991-2007).
 Cesarean delivery is defined as the delivery of a fetus through surgical incisions made through the abdominal wall (laparotomy) and the uterine wall (hysterotomy). Because the words "cesarean" and "section" are both derived from verbs that mean to cut, the phrase "cesarean section" is a tautology. Consequently, the terms "cesarean delivery" and "cesarean birth" are preferable. Cesarean deliveries were initially performed to separate the mother and the fetus in an attempt to save the fetus of a moribund patient. This operation subsequently developed into a surgical procedure to resolve maternal or fetal complications not amenable to vaginal delivery, either for mechanical limitations or to temporize delivery for maternal or fetal benefit. The cesarean delivery has evolved from a vain attempt performed to save the fetus to one in which physician and patient both participate in the decision-making process, striving to achieve the most benefit for the patient and her unborn child. Currently, cesarean deliveries are performed for a variety of fetal and maternal indications (see Indications). The indications have expanded to consider the patient’s wishes and preferences. Controversy surrounds the current rates of cesarean delivery in developed countries and its use for indications other than medical necessity.Go to Perimortem Cesarean Delivery and Vaginal Birth After Cesarean Delivery for complete information on these topics. From 1910-1928, the cesarean delivery rate at Chicago Lying-in Hospital increased from 0.6% to 3%. The cesarean delivery rate in the United States was 4.5% in 1965. According to the National Hospital Discharge Survey, the cesarean rate rose from 5.5% in 1970 to 24.1% in 1986. Fewer than 10% of mothers had a vaginal birth after a prior cesarean, and women spent an average of 5 days in the hospital for a cesarean delivery and only 2.6 days for a vaginal delivery. It was predicted that if age-specific cesarean rates continued at the steady pattern of increase observed since 1970, 40% of births would be by cesarean in the year 2000. [19] Those predictions fell short, but not by much. The National Center for Health Statistics reported that the percentage of cesarean births in the United States increased from 20.7% in 1996 to 32.2% in 2014. [1, 20] Cesarean rates increased for women of all ages, races/ethnic groups, and gestational ages and in all states (see the image below). Both primary and repeat cesareans increased.
Increases in the primary cesareans with no specified indication were faster than in the overall population and appear to be the result of changes in obstetric practice rather than changes in the medical risk profile or increases in maternal request. [21] This has occurred despite several studies that note an increased risk for neonatal and maternal mortality for all cesarean deliveries as well as for medically elective cesareans compared with vaginal births. [22] The decrease in total and repeat cesarean delivery rates noted between 1990 and 2000 was due to a transient increase in the rate of vaginal births after cesarean delivery. [23] The cesarean delivery rate has also increased throughout the world, but rates in certain parts of the world are still substantially lower than in the United States. The cesarean delivery rate is approximately 21.1% for the most developed regions of the globe, 14.3% for the less developed regions, and 2% for the least developed regions. [24] In a 2006 publication reviewing cesarean delivery rates in South America, the median rate was 33% with rates fluctuating between 28% and 75% depending on public service versus a private provider. The authors conclude that higher rates of cesarean delivery do not necessarily indicate better perinatal care and can be associated with harm. [25] Why the rate of cesarean delivery has increased so dramatically in the United States is not entirely clear. Some reasons that may account for the increase are repeat cesarean delivery, delay in childbirth and reduced parity, decrease in the rate of vaginal breech delivery, decreased perinatal mortality with cesarean delivery, nonreassuring fetal heart rate testing, and fear of malpractice litigation, as described in the following paragraphs. In 1988, when the cesarean delivery rate peaked at 24.7%, 36.3% (351,000) of all cesarean deliveries were repeat procedures. Although reports concerning the safety of allowing vaginal birth after a cesarean delivery had been present since the 1960s, [26] by 1987, fewer than 10% of women with a prior cesarean delivery were attempting a vaginal delivery. In 2003, the repeat cesarean delivery rate for all women was 89.4%; the rate for low-risk women was 88.7%. Today, low-risk women giving birth for the first time who have a cesarean delivery are more likely to have a subsequent cesarean delivery. [27] In the past decade, an increase in the percentage of births to women aged 30-50 years has occurred despite a decrease in their relative size within the population. [28] The cesarean rate for mothers aged 40-54 years in 2007 was more than twice the cesarean rate for mothers younger than 20 years (48% and 23%, respectively). [28] The risk of having a cesarean delivery is higher in nulliparous patients, and, with increasing maternal age, the risk for cesarean delivery is increased secondary to medical complications such as diabetes and preeclampsia. By 1985, almost 85% of all breech presentations (3% of term fetuses) were delivered by cesarean. In 2001, a multicenter and multinational prospective study determined that the safest mode of delivery for a breech presentation was cesarean delivery. [29] This study has been criticized for differences in the standards of care among the study centers that does not allow a standard recommendation. [30] The most recent recommendation from the American College of Obstetricians and Gynecologists (ACOG) regarding breech delivery is that planned vaginal delivery may be reasonable under hospital-specific protocol guidelines for both eligibility and labor management. [31] This may lead to a small decrease in breech delivery rates, but the overwhelming majority of cases will probably continue to be delivered by elective cesarean. A cluster-randomized controlled trial by Chaillet et al reported a significant but small reduction in the rate of cesarean delivery. The benefit was driven by the effect of the intervention in low-risk pregnancies. [32, 33] Many indications exist for performing a cesarean delivery. In those women who are having a scheduled procedure (ie, an elective or indicated repeat, for malpresentation or placental abnormalities), the decision has already been made that the alternate of medical therapy, ie, a vaginal delivery, is least optimal. For other patients admitted to labor and delivery, the anticipation is for a vaginal delivery. Every patient admitted in this circumstance is admitted with the thought of a successful vaginal delivery. However, if the patient’s situation should change, a cesarean delivery is performed because it is believed that outcome may be better for the fetus, the mother, or both. A cesarean delivery is performed for maternal indications, fetal indications, or both. The leading indications for cesarean delivery are previous cesarean delivery, breech presentation, dystocia, and fetal distress. These indications are responsible for 85% of all cesarean deliveries. [7] Maternal indications for cesarean delivery include the following:
Relative maternal indications include conditions in which the increasing intrathoracic pressure generated by Valsalva maneuvers could lead to maternal complications. These include left heart valvular stenosis, dilated aortic valve root, certain cerebral arteriovenous malformations (AVMs), [8] and recent retinal detachment. Women who have previously undergone vaginal or perineal reparative surgery (eg, colporrhaphy or repair of major anal involvement from inflammatory bowel disease) also benefit from cesarean delivery to avoid damage to the previous surgical repair. No clear evidence supports planned cesarean delivery for extreme maternal obesity. A prospective cohort study from the United Kingdom included women with a body mass index of 50 kg/m2 or more and noted possible increased shoulder dystocia (3% vs 0%) but found no significant differences in anesthetic, postnatal, or neonatal complications between women who underwent planned vaginal delivery and those who underwent planned caesarean delivery. [34] However recent studies indicate that obese and extremly obese women have an increased odds ration of having a cesarean section, 2.05 and 2.89 compared with normal weight women. [35] Dystocia in labor (labor dystocia) is a very commonly cited indication for cesarean delivery, but it is not specific. Dystocia is classified as a protraction disorder or as an arrest disorder. These can be primary or secondary disorders. Most dystocias are caused by abnormalities of the power (uterine contractions), the passage (maternal pelvis), or the passenger (the fetus). [36] When a diagnosis of dystocia in labor is made, the indication should be detailed according to the previous classification (ie, primary or secondary disorder, arrest or protraction disorder, or a combination of the above). For further information, see Abnormal Labor. Recently, debate has arisen over the option of elective cesarean delivery on maternal request (CDMR). Evidence shows that it is reasonable to inform the pregnant woman requesting a cesarean delivery of the associated risks and benefits for the current and any subsequent pregnancies. The clinician’s role should be to provide the best possible evidence-based counseling to the woman and to respect her autonomy and decision-making capabilities when considering route of delivery. [37] In 2006, the National Institutes of Health (NIH) convened a consensus conference to address CDMR. They resolved that the evidence supporting this concept was not conclusive. [10] Their recommendations included the following:
The NIH further noted that the procedure requires individualized counseling by the practitioner of the potential risks and benefits of both vaginal and cesarean delivery, and it should not be motivated by the unavailability of effective pain management. [10] Detractors of CDMR argue that the premise of cesarean on request applies to a very small portion of the population and that it should not be routinely offered on ethical grounds. [39] The emerging consensus is that a randomized prospective study is required to address this issue. [40] Fetal indications for cesarean delivery include the following:
A fetus in a nonvertex presentation is at increased risk for trauma, cord prolapse, and head entrapment. Malpresentation includes preterm breech presentations and non-frank breech term fetuses. The decision to proceed with a cesarean delivery for the term frank breech singleton fetus has been challenged. Although most practitioners will always perform a cesarean delivery in this situation, ACOG has left open the option to consider a breech delivery under the appropriate circumstances, including a practitioner experienced in the evaluation and management of labor and skilled in the delivery of the breech fetus. [31] Some state maternal care collaborative agencies are even implementing tools to decrease the likelihoond of cesarean section in the instance of a breech presentation, with guidelines recommending the formation of a team in the hospital that is trained and confortable with breach and operative deliveries. [41] If a patient is diagnosed with a fetal malpresentation (ie, breech or transverse lie) after 36 weeks, the option for an external cephalic version is offered to try to convert the fetus to a vertex lie, thus allowing an attempt at a vaginal delivery. An external cephalic version is usually attempted at 36-38 weeks with studies underway to establish the use of performing external cephalic version at 34 weeks’ gestational age. Ultrasonography is performed to confirm a breech presentation. If the fetus is still in a nonvertex presentation, an intravenous (IV) line is started, and the baby is monitored with an external fetal heart rate monitor prior to the procedure to confirm well-being. With a reassuring fetal heart rate tracing, the version is attempted. An external cephalic version involves trying to externally manipulate the fetus into a vertex presentation. This is accomplished with ultrasonographic guidance to ascertain fetal lie. An attempt is made to manipulate the fetus through either a "forward roll" or "backward roll." The overall chance of success is approximately 60%. [42] Some practitioners administer an epidural to the patient before attempting version, and others may give the patient a dose of subcutaneous terbutaline (a beta-mimetic used for tocolysis) just before the attempt. Factors that influence the success of an attempted version include multiparity, a posterior placenta, and normal amniotic fluid with a normally grown fetus. In addition, to be a candidate, a patient must be eligible for an attempted vaginal delivery. Contraindications to external cephalic version inlclude oligohydramnios, intrauterine growth restriction with abnormal doppler or fetal heart tracing, major uterine anomalies, antepartum hemorrhage, abnormal fetal heart tracing, multiparity and rupture of memebrane. [43] Relative contraindications include poor fetal growth or the presence of congenital anomalies. Risks of an external cephalic version include rupture of membranes, labor, fetal injury, and the need for an emergent cesarean delivery due to placental abruption. A recent review reported a severe complication rate of 0.24% and a cesarean section rate secondary to complications of 0.34%. [42] If the version is successful, the patient is placed on a fetal monitor in close proximity to the labor and delivery unit or in the labor and delivery unit itself. If fetal heart rate testing is reassuring, the patient is discharged to await spontaneous labor, or she may be induced if the fetus is of an appropriate gestational age or the patient has a favorable cervix. The first twin in a nonvertex presentation is an indication for a cesarean delivery, as are higher order multiples (triplets or greater). A large body of literature supports both outright cesarean delivery as well as spontaneous breech delivery or extraction of the second twin. The decision is made in conjunction with the patient after appropriate counseling regarding the risks and benefits as well as under the supervision of a physician experienced in the management of the labor and delivery of a breech fetus. [44] Evidence suggests that the rate of severe complications of the second breech twin is independent of the mode of delivery. [45] Several congenital anomalies are controversial indications for cesarean delivery; these include fetal neural tube defects (to avoid sac rupture), particularly defects that are larger than 5-6 cm in diameter. One study noted no difference in long-term motor or neurologic outcomes. [46] Some authors noted no relationship between mode of delivery and infant outcomes, [47] while others have advocated cesarean delivery of all infants with a neural tube defect. [48] Cesarean delivery is indicated in certain cases of hydrocephalus with an enlarged biparietal diameter, and some skeletal dysplasias such as type III osteogenesis imperfecta. Whether or not an outright cesarean delivery should be performed in the setting of a fetal abdominal wall defect (eg, gastroschisis or omphalocele) remains controversial. Most reviews agree that cesarean is not advantageous unless the liver is extruded, which is a very rare event. [49, 50, 51] The overall incidence of cesarean delivery in this group of patients is probably due to an increased incidence of intrauterine growth retardation and fetal distress prior to or in labor. In the setting of a nonremediable and nonreassuring pattern remote from delivery, a cesarean delivery is recommended to prevent a mixed or metabolic acidemia that could potentially cause significant morbidity and mortality. Electronic fetal monitoring was used in 85% of labors in the United States in 2002. [52] Its use has increased the cesarean delivery rate as much as 40%. [53] This has occurred without a decrease in the cerebral palsy or perinatal death rate. [54] ACOG has recommended that any facility providing obstetric care have the capability of performing a cesarean delivery within 30 minutes of the decision. Despite this recommendation, a decision to delivery time of more than 30 minutes is not necessarily associated with a negative neonatal outcome. [55] Among patients with first-episode genital herpes infection, the risk of maternal-fetal transmission is 33 times higher than with recurrent outbreaks. The largest population-based study reported that for primary infection, the risk of transmission to the newborn was 35%, compared with a 2% risk for recurrent infection. Among patients with culture-positive herpes, the transmission rate with vaginal delivery was 7 times that with cesarean delivery. Currently, all patients with active or symptomatic herpes infection are candidates for cesarean delivery. [56] Neonatal infection with herpes can lead to significant morbidity and mortality, especially with a primary outbreak. With recurrent outbreaks, the risk to the neonate is reduced by the presence of maternal antibodies. Unfortunately, not all women with active viral shedding can be detected upon admission to labor and delivery. Treatment of women with HIV infections has undergone tremendous change in the past few years. Women with a viral count above 1,000 should be offered cesarean delivery at 38 weeks (or earlier if they go into labor). In women who are being treated with highly active antiretroviral therapy (HAART), cesarean delivery (before labor or without prolonged rupture of membranes) appears to further lower the risk for neonatal transmission, particularly among those with viral counts above 1,000. Among patients with low or undetectable viral counts, the evidence supporting a benefit is not as clear; nevertheless, the patient should be given the option of a cesarean delivery. [57] Indications for cesarean delivery that benefit both the mother and the fetus include the following:
In the presence of a placenta previa (ie, the placenta covering the internal cervical os), attempting vaginal delivery places both the mother and the fetus at risk for hemorrhagic complications. This complication has actually increased as a result of the increased incidence of repeat cesarean deliveries, which is a risk factor for placenta previa and placenta accreta. Both placenta previa and placenta accreta carry increased morbidity related to hemorrhage and need for hysterectomy. [58, 59, 38] Cephalopelvic disproportion can be suspected on the basis of possible macrosomia or an arrest of labor despite augmentation. Many cases diagnosed as cephalopelvic disproportion are the result of a primary or secondary arrest of dilatation or arrest of descent. Predicting true primary or secondary arrest of descent due to cephalopelvic disproportion is best assessed by sagittal suture overlap, but not lambdoid suture overlap, particularly where progress is poor in a trial of labor. [60] Continuing to attempt a vaginal delivery in this setting increases the risk of infectious complications to both mother and fetus from prolonged rupture of membranes. [61] Less often, maternal hemorrhagic and fetal metabolic consequences occur from a uterine rupture, especially among patients with a previous cesarean delivery. [18] Vaginal delivery can also increase the risk of maternal trauma and fetal trauma (eg, Erb-Duchenne or Klumpke palsy and metabolic acidosis) from a shoulder dystocia. [62, 63] Among women who have a uterine scar (prior transmural myomectomy or cesarean delivery by high vertical incision), a cesarean delivery should be performed prior to the onset of labor to prevent the risk of uterine rupture, which is approximately 4-10%. [18] There are few contraindications to performing a cesarean delivery. If the fetus is alive and of viable gestational age, then cesarean delivery can be performed in the appropriate setting. In some instances, a cesarean delivery should be avoided. Rarely, maternal status may be compromised (eg, with severe pulmonary disease) to such an extent that an operation may jeopardize maternal survival. In such difficult situations, a care plan outlining when and if to intervene should be made with the family in the setting of a multidisciplinary meeting. A cesarean delivery may not be recommended if the fetus has a known karyotypic abnormality or known congenital anomaly that may lead to death (anencephaly). However, the physician and the patient must actively discuss all the options prior to making that decision. |
Which findings would the nurse monitor for in a patient who has undergone a cesarean section
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