An international survey on cesarean delivery rates showed dramatic variability among regions as well as between developed and less developed countries (1). The survey collected data on maternal, fetal and neonatal mortality, incidence as a percentage of births and the presence of a trained health professional, which represented a measure of obstetric care afforded to the population. Data were collected for 126 countries and the authors estimated that they were able to capture 89% of all live births for 2002. Those countries were organized into regional and subregional categories using United Nations criteria, and the cesarean delivery rates were reported within those categories (Table 12-1). Taken together, the surveys indicated an overall international incidence of 15%. However, there was significant variance between and within regional categories and level of development among countries.

In developed regions such as Western Europe, North America, Australia, and New Zealand, cesarean rates averaged well over the worldwide figure of 15%. Taking developed countries as a whole, the mean rate was reported as 21.1%. In the United States, primary and repeat rates have increased steadily from 5.5% in 1970 to 32% in 2007 (6,7). Zhang et al. (8) reported an overall cesarean rate of 30.5% in the United States between 2002 and 2008. But cesarean deliveries varied significantly among the various hospitals surveyed with rates ranging from 20% to 44%. In other regions such as Canada, rates increased from 17.8% to 19.1% from 1994 to 1997 (9), and in England and Wales, the rate increased from 16% to 19% to 21.5% in 1995, 1999, and 2000, respectively (10).

In less developed regions, the mean cesarean delivery rate hovered about 15%, again with marked variation among regions and subregions. In the least developed regions, as defined by 49 countries located mostly in Africa, the average cesarean delivery rate was 2% (1). Here, an association of low cesarean delivery rates and high maternal mortality rates was supported, with some exceptions.

Alarmed at the rapid rise in cesarean delivery rates, in 1985 the World Health Organization made the recommendation that information about cesarean delivery rates at obstetric institutions should be made available to the public (11). The assumption was that by informing mothers of the potential negative effects of cesarean deliveries and then publishing institutional data, those rates would fall. The WHO report noted that countries with rates less than 10% had some of the lowest perinatal mortality rates in the world, stating “there is no justification for any region to have a rate higher than 10–15%.” Despite this very public attempt to reduce cesarean delivery rates, the trend has shown a distinctive increase.

The reasons for the rising cesarean rates in developed countries appear to be complex and numerous but do not vary greatly among most industrialized countries suggesting a commonality of influences. Joseph et al. (9) reviewed the indications for all primary cesarean deliveries in Nova Scotia, Canada between 1988 and 2000. They found that changes in maternal characteristics, maternal comorbidities, and obstetric practice were responsible for the rise in primary cesarean delivery rates (Table 12-2). The maternal characteristics identified were increasing age, lower parity, higher prepregnancy weight and greater weight gain during pregnancy. Of reasons cited for a primary cesarean delivery, the most significant increases were for dystocia and breech presentation. Concurrent maternal comorbidities contributing to greater maternal risk were also implicated in driving the rate upward. These findings were supported by others noting that more women were choosing to follow a career path
and delay marriage and family. Thus, the average age of nulliparity has risen over the past two decades and public health analyses confirm that women of advanced maternal age are more likely to have a cesarean delivery (12). Menacker et al. concurred with all of the aforementioned reasons and added concerns over litigation and more conservative recommendations from medical associations as contributing to the rising rate from 1991 to 2007 in the United States. Cesarean delivery rates in 2007 were at the highest ever recorded in the United States at 32%, and represented a 53% increase from rates 16 years previously (13). In some states, rates increased by over 70%.

Obstetric practice has changed over time with more technology available to assist in labor management, and a better awareness by obstetric providers of maternal safety and outcomes. Breech presentations are rarely performed vaginally for a variety of reasons including poor maternal and neonatal outcomes, fear of litigation, and obstetric society publications suggesting a better outcome with cesarean delivery (14,15). The decreased use of forceps as well as the greater use of fetal monitoring in obstetric practice leading to variable interpretations of abnormal fetal traces have led to more cesarean deliveries (6,9,13). In the United States in 2004, fully one in three nulliparous women were delivered by cesarean delivery (8). In this report by Zhang et al., a statistically significant contributing factor was the elective induction of labor especially without a clear obstetric or medical indication.

When the 1985 WHO recommendations were published, along with promulgating a 10% to 15% cesarean delivery rate, the concept of always requiring a cesarean following the first was debunked (11). As a means to achieve a lower surgical delivery rate, the concept of a vaginal birth after cesarean (VBAC) was endorsed. There followed a brief drop in the overall rate during the early 1990s as women were counseled to attempt a VBAC. However, VBAC rates began to drop off in 1996 and cesarean rates rose for reasons of perceived maternal safety. Macones et al. (16) performed a retrospective observational study of more than 25,000 women who had previously had cesarean delivery. They reported that the incidence of uterine rupture for a low transverse incision was 9.8/1,000, and that if a woman had a previous successful VBAC, the incidence of uterine rupture was further lowered. Regardless, VBAC rates fell and in an editorial response 3 years later to an article on the diminishing rate of VBAC delivery in the United States, Macones (17) suggested that the factor driving the decision making among obstetricians and their patients was an overly emphasized concern about uterine rupture. He pointed out that the current evidence-based rates placed the risk of uterine rupture at 0.5% to 1%, and the neonatal risk of hypoxic ischemic encephalopathy at 12/15,000. Macones also stressed the longer-term risks of placenta previa or placenta accreta with increasing numbers of cesarean deliveries. Despite the data, more current numbers show that VBAC rates remain low. Women with a previous cesarean delivery undergo a trial of labor in 28.8% of possible cases when estimates are that two-thirds of women with uterine scars are eligible (8). Among those who attempt a VBAC, only 57.1% of them have a successful vaginal birth. Thus, 83.6% of women in 2004, who had a previous cesarean delivery, were delivered by repeat cesarean delivery.

An oft-quoted explanation for the rise in cesarean deliveries is the corresponding rise in litigation for poor maternal or neonatal outcomes (9,18,19). Litigation pressures are positively correlated with rising cesarean delivery rates in industrialized countries including the United States and negatively correlated with VBAC delivery (18). Murthy et al. reported that an indirect measure of the effect of litigation on medical practice is to measure the professional liability premiums. They analyzed the rate of rise of medical professional liability premiums in Illinois between 1998 and 2003 against the primary cesarean delivery over that same time period and reported a positive correlation between rising primary cesarean rates and rising premiums both in nulliparous and multiparous women (19).

Another relatively recent yet concerning trend has been the occurrence of maternal request for an elective cesarean delivery, thereby avoiding a vaginal attempt. Habiba et al. (20) surveyed obstetricians from eight European countries and inquired how they would respond to a woman’s request for elective cesarean delivery without any obstetric or medical indication. Countries whose obstetricians were likely to agree to such a request were Germany and the United Kingdom. Those countries where obstetricians were least likely to consent to the same were Spain and France. These authors suggested that cultural differences and fear of litigation were important factors in determining whether the providers in a particular country would be willing to perform an elective cesarean without indication. Some suggest that the mother’s perception of the optimal delivery method for her baby influences her decision of the mode of delivery. With this in mind, a Lancet editorial written in response to the growing national debate over maternal request in the United Kingdom suggested that a mother who is well informed about the indications and consequences of cesarean delivery would be less inclined to want cesarean delivery when it was not indicated, and if well informed would be more amenable to undergoing a trial of labor after cesarean delivery (TOLAC). However, a survey quoted in that editorial reported that when the female obstetricians in 31 hospitals in the United Kingdom were asked what mode of delivery they would prefer if they were pregnant, 31% answered they would choose an elective cesarean delivery despite a lack of indication. This suggested that even the well-informed mother may make requests based on personal preference despite the evidence of no benefit but substantially more risk of morbidity and mortality (21).

Whether elective or not, cesarean deliveries expose the mother to an assortment of potential short- and long-term risks. Kainu et al. demonstrated in a cohort study of 600 patients that persistent pain 1 year after delivery was more common in those who had a cesarean delivery compared to a vaginal birth (22). Although rare, bladder and ureteral injuries are greater with cesarean than vaginal delivery and there is a significantly increased risk of postpartum endometritis in patients who have undergone surgery over a vaginal delivery (23). Women are less likely to have symptoms of urinary incontinence or pelvic floor dysfunction after elective cesarean delivery provided no labor has occurred as compared to women who have labored. This statistic is quoted at times as the reason for maternal request. Yet it has been shown that if a woman has a cesarean delivery for obstructed labor, she risks a similar incidence of urinary incontinence as those who had a vaginal delivery (24). As the presence of a uterine scar increases the risk of abnormal implantation of the placenta, the increased risk of a placenta previa and/or accreta is significant for future pregnancies (17).

Overall maternal mortality has decreased significantly over the last century but not necessarily because of the rise in cesarean delivery. Deneaux et al. (25) performed a case-control analysis of the incidence of postpartum maternal death in French women who had a cesarean delivery and compared the rate of death following a vaginal delivery. They reported that the risk of postpartum death was 3.6 times higher following a cesarean compared to a vaginal delivery. Anesthetic
causes were implicated in four cases of maternal death during a cesarean delivery of which general anesthesia was implicated in three cases and spinal anesthesia in only one. Studies in other countries also report an increased risk to a mother’s health with cesarean delivery over vaginal. The 2001 Confidential Enquiry into Maternal Deaths, a triennial report from the Royal College of Obstetricians and Gynaecologists on adverse maternal outcomes in Great Britain, calculated that an elective cesarean delivery is associated with a 2.84 times greater incidence of maternal death than a vaginal delivery.

Regardless of the mode of delivery, the maternal mortality rate in the United States in 2007 was 12.7/100,000 live births (26). Clark et al. (27) specifically investigated the causes of maternal death in the United States between 2000 and 2006 that were related to cesarean delivery. They reported that the maternal mortality rate from all causes was 0.2/100,000 vaginal deliveries and 2.2/100,000 cesarean deliveries. Upon examination of the causes of deaths, they reported that a significant number were due to thromboembolic complications. They further calculated that if these thromboembolic events had been prevented, the incidence of maternal death due to cesarean delivery would fall to 0.9/100,000 cesarean deliveries. This would make the maternal mortality rate between cesarean and vaginal deliveries comparable. Even with such preventative measures, Clark et al. noted that whether the delivery mode is vaginal or surgical, most maternal deaths are not preventable.

There is no evidence that a cesarean delivery leads to a better neonatal outcome over a vaginal delivery. The epidemiologic study of Villar et al. (5) that involved 97,095 births within eight Latin American countries suggested that as the cesarean delivery rate rose from 10% to 20%, there was an increase in the number of admissions to the neonatal intensive care units (ICU) for 7 days or longer. There may be an optimum cesarean delivery rate at which overall maternal and fetal morbidity and mortality are minimized but this has not yet been defined. Several reports indicate that a cesarean delivery rate greater than 15% may be associated with increased maternal and fetal morbidity and mortality (1,7,11).

Other studies have examined whether cesarean delivery has a negative association on the long-term outcome of neonates. Leung et al. (28) questioned whether cesarean delivery impacted pediatric morbidity by looking at outpatient care or hospital admission (15). This epidemiologic study involved 5,449 term singleton infants from a Chinese post-industrialized community. Once all potential confounders were accounted for, the authors found no association between cesarean delivery and the frequency of outpatient visits or hospital admissions during the first 18 months of the child’s life. They concluded that the mode of delivery did not have an effect on the morbidity or mortality of an infant’s life during the first 18 months.

The incidence of cesarean delivery is increasing worldwide particularly in developed countries. The reasons for this increase are complex as discussed. It has been suggested that the best way to slow the increasing cesarean delivery rate is to target low risk mothers with term, singleton, and vertex presentations. Evidence suggests that permitting only indicated inductions or allowing spontaneous labor would improve vaginal delivery numbers. Also, not acceding to maternal requests for non-indicated surgical deliveries would be a significant influence. Another group of parturients to target are those with a previous cesarean delivery who qualify for a TOLAC (13). Under the correct conditions, maternal risks are minimal and a TOLAC can be performed safely with a reasonable expectation of success. This would prevent these patients from being relegated to cesarean delivery for future deliveries with its associated risks.

Because the unexpected can occur quickly in obstetrics, it is always best to have a baseline assessment before any procedure. Thus a complete preanesthetic evaluation should include not only a thorough history but a physical examination that evaluates the airway, lungs, and heart, at the very least. Examination of other areas should be directed by the patient’s history and anesthetic plan. For a complete discussion of the airway examination and approaches to the difficult airway, please see Chapter 23.

Informed consent is a discussion with the patient that consists of five components: A presentation of the proposed
anesthetic, a discussion of the risks and benefits, a presentation of the alternatives to the plan, and the opportunity for the patient to have all her questions asked and answered to her satisfaction. The question has been raised whether the obstetric patient can make an informed decision while experiencing labor pain or coping with an urgent or emergency situation requiring a rapid response. Opinion at this time is that there is no evidence that she cannot. Thus, unless the situation presents an immediate threat to the life of the mother or fetus, every parturient should go through the informed consent process prior to any anesthetic.

There is no evidence that any particular laboratory test such as a platelet count or hematocrit is necessary for a healthy parturient undergoing a routine cesarean delivery. The selection of laboratory studies should be determined by the maternal history or clinical situation. Although it has been common practice in the past to routinely request a platelet count prior to the initiation of a neuraxial anesthetic, best evidence shows that doing so is unwarranted in a patient with a benign history and examination (29). Equally unnecessary is to have a full type and crossmatch completed prior to a routine surgical delivery. However, having a completed type and screen or blood sample in the blood bank is considered reasonable.

If the patient’s history warrants a platelet count prior to a neuraxial block, the next issue to consider is what the lower limit to the count is placement contraindicated because of concerns of a hematoma. The “100,000-rule” that was adhered to for so long has no scientific basis, and it is now felt by most anesthesiologists that 80 × 10⁹/L (“80,000”) is safe. However, there is no objective or outcome-based evidence for that belief either, and unfortunately there are no established bedside tests that can be used to evaluate platelet function. The bleeding time of old is no longer considered valid but neither the platelet function analyzer (PFA) nor the thromboelastogram (TEG) has been validated by adequate study designs and sample sizes either. Studies to evaluate the usefulness of these two methods have been based on small population sizes. Thus, more work is necessary before any recommendations on these devices can be made (30).

Both the US and British Hematological Societies have suggested a lower count that is tolerable in situations of idiopathic thrombocytopenic purpura. The British Committee for Standards in Haematology published guidelines stating that platelet counts of 50 × 10⁹/L are safe for a vaginal delivery and 80 × 10⁹/L for cesarean delivery and neuraxial anesthesia (31). The American College for Hematology guidelines state 50 × 10⁹/L as safe, and make no distinction between vaginal delivery, cesarean delivery, and neuraxial anesthesia (32). There remains a lack of adequate data behind these recommendations, but increasing numbers of anesthesia providers are comfortable performing a neuraxial block in the presence of a count below 100 × 10⁹/L in a patient without a bleeding history (30), and some recommend as low as 50 × 10⁹/L in parturients with non-preeclamptic thrombocytopenia (33,34).

Intravenous access must be adequate to allow for effective resuscitation in the event of hemorrhage. Large-bore intravenous catheters (16 or 18 gauge) allow for rapid fluid resuscitation and blood administration if the need arises. Preloading with fluid prior to the initiation of neuraxial anesthesia is not obligatory and should not preclude the initiation of the block. Dyer et al. (35) demonstrated that rapid co-loading with 20 mL/kg crystalloid at the time of neuraxial placement was as effective as preloading. Although significant hypotension following a spinal anesthetic is a common complication, not all parturients have this complication to a significant extent, and it is difficult to predict who will. Regardless, this complication is readily corrected with fluids and vasopressors, of which ephedrine, phenylephrine, or a combination of both are preferred in the United States (29).

The ASA Practice Guidelines for Obstetric Anesthesia state that equipment, monitors, facilities, and support personnel should be similar to those available in the main operating room facility (29). Patients undergoing a cesarean delivery or any operative procedure should be monitored as defined by ASA standards and fetal monitors and neonatal resuscitative equipment should be in or adjacent to all operative sites. Equipment necessary for maternal resuscitation should also meet facility standards, and items such as an air warmer, fluid warmer, rapid infuser, and resuscitative equipment should be in the operating room or nearby and ready for use. Given the greater potential difficulties of the obstetric airway, a “Difficult Airway Cart” should be fully stocked, routinely checked, and immediately available to the operating area.

The risk of aspiration, techniques of prophylaxis, and consideration of NPO policies are discussed extensively in Chapter 24. In this section, the specific practices for prophylaxis relating to cesarean delivery are considered. Modern obstetric anesthesia practice and guidelines have changed with a better understanding of gastrointestinal physiology in the pregnant patient (29). Current recommendations allow for the consumption of modest amounts of clear liquids until 2 hours before an uncomplicated elective cesarean delivery in non-laboring patients. Obviously, those with known gastric dysfunction or risk factors for aspiration will require more prolonged fasting or treatment as “full stomach” (at risk for aspiration). As for the ingestion of solid foods, current recommendations are that patients should fast for 6 to 8 hours depending on the fat content of the meal consumed prior to an elective uncomplicated cesarean delivery. Because any laboring patient may need an urgent or emergent cesarean, and because it has been shown that eating even light solid food during labor increases gastric volume and amount of vomitus (36), it is common practice in many centers to discourage solid intake during labor. When it may not be possible to wait the recommended 6 to 8 hours in a non-elective cesarean situation, it may be prudent to allow as much time to elapse as is safe, and agents to neutralize gastric acid and perhaps to promote gastric emptying should be utilized.

Early studies supported the effectiveness of non-particulate antacids such as sodium citrate to increase gastric pH but did so at the cost of increasing gastric volume. However, effectiveness is related to timing of administration. Dewan et al. (37) evaluated the optimal timing and efficacy of sodium citrate in increasing gastric pH prior to cesarean delivery. They randomized 32 patients receiving general anesthesia to receive 30 mL 0.3 M sodium citrate either less than 60 minutes before surgery, greater than 60 minutes before surgery, or immediately after delivery of the baby. Their results demonstrated that sodium citrate must be administered within 60 minutes of the start of surgery in order to be effective in raising pH, although gastric volumes were similar in all groups. As H₂ receptor antagonists became available, studies determined that they are effective in increasing gastric
pH and do not add to gastric volumes. Rout et al. (38) studied whether it was best to use both or only one agent. They evaluated the efficacy of ranitidine and sodium citrate compared to citrate alone. Patients scheduled to undergo a non-elective cesarean delivery with general anesthesia received ranitidine or placebo at the time of the decision to operate followed by sodium citrate as they entered the operating room. The authors found that if 30 minutes had elapsed from the administration of ranitidine to induction of anesthesia, patients were at significantly less risk for aspiration, though defined by liberal criteria (pH >3.5, volume >25 mL), and only pre-extubation and not post-intubation. Lin et al. (39) compared the efficacy of H₂ receptor antagonists and proton pump inhibitors in neutralizing gastric acidity in patients undergoing an elective cesarean delivery under spinal anesthesia. They randomized 160 patients to receive orally either a placebo, famotidine 40 mg, ranitidine 300 mg, or omeprazole 40 mg at least 3 hours before surgery. They determined that omeprazole was not effective at neutralizing gastric acid and that it resulted in the largest gastric volumes. However, the H₂ antagonists, famotidine and ranitidine, were equally effective.

A recent Cochrane review evaluated current evidence of the effectiveness of prophylactic agents against acid aspiration (40). The authors reported that although the available studies were of poor quality, current evidence supports the combination of H₂ receptor antagonists and antacids as being more effective than either one alone or no prophylaxis. Proton pump inhibitors were not very effective, and the prokinetic drug, metoclopramide, did not seem useful either. Moreover, de Souza et al. (41) have argued against cricoid pressure in preventing aspiration in elective cesarean delivery. Taken together, best evidence suggests that administering some agent for aspiration prophylaxis is likely warranted, particularly in laboring patients, and that multimodal therapy is better than a single agent in raising surrogate measures of aspiration risk such as gastric pH. The best support is for the use of an H₂ antagonist 30 minutes before and a non-particulate antacid closer to the procedure. The lack of evidence for differences in outcome, however, suggests that other regimens should be considered acceptable.

Postpartum infection is 5 to 20 times more frequent in patients who have had cesarean delivery than in those who have had a vaginal delivery (42). Which antibiotic is the best choice and when to give it are important issues to determine before proceeding with cesarean delivery. Currently, the antibiotic of choice in the United States is a cephalosporin. However, a recent Cochrane review reported that cephalosporins are equivalent to penicillins in preventing immediate post-cesarean infections (43). This was supported by evidence from 25 randomized controlled trials but the quality of the trials was reported as weak. They also noted that there were no data to support an antibiotic class that was best to prevent neonatal or late maternal infections.

Until recently, all antibiotics for a cesarean delivery were given after the cord was clamped to avoid exposing the neonate to antibiotics and thus potentially cloud signs of impending sepsis. Current national standards in the United States promote pre-incisional timing of antibiotic as an important practice to prevent postoperative infections. Tita et al. (44) reviewed the current literature examining antibiotic prophylaxis during cesarean delivery. They performed a meta-analysis of various randomized controlled trials and other meta-analyses and found that whether a narrow spectrum antibiotic such as cefazolin was given prior to surgical incision or an extended-spectrum antibiotic such as azithromycin or metronidazole was given after clamping of the umbilical cord, both approaches appeared equally effective in preventing postoperative infection by 50%. This was in contrast to the traditional practice of administering a narrower spectrum antibiotic such as cefazolin after clamping of the umbilical cord. However, they reported no evidence on the risk of infection in the neonate or infection due to resistant bacteria. Numerous other randomized trials have confirmed the advantage of pre-incision administration (45) and ACOG now recommends this timing (46). As it is less expensive to administer a cephalosporin, current recommendations are to give cefazolin 2 g before the incision. If the patient is cephalosporin-allergic, clindamycin together with gentamicin is the preferred choice regardless of any other antibiotic given earlier for another infection source.