Version July 2025
INTRODUCTION —
Cesarean birth is one of the most common surgical procedures performed worldwide and comprises almost one-third of all births in the United States [1].
This topic will review preoperative planning and patient preparation for these births. Several related issues are discussed separately:
●(See "Cesarean birth: Surgical technique".)
●(See "Cesarean birth: Overview of issues for patients with obesity".)
●(See "Cesarean birth: Postoperative care, complications, and long-term sequelae".)
●(See "Repeat cesarean birth".)
●(See "Choosing the route of delivery after cesarean birth".)
●(See "Optimal cesarean birth rate".)
Our approach is generally consistent with other evidenced-based protocols. The Enhanced Recovery After Surgery (ERAS) Society has published guidelines for perioperative care of patients undergoing cesarean birth, the ERAS Cesarean Delivery Guidelines, which cover the time from the decision to operate (starting with the 30 to 60 minutes before skin incision) to hospital discharge [2-4]. The American College of Obstetricians and Gynecologists (ACOG) has published a guideline for enhanced recovery after surgery [5]. Other organizations and many hospitals have also created such guidelines/pathways [6,7]. These approaches appear to reduce postoperative complications, reduce postoperative pain scores and opioid use, and shorten hospital stay without compromising readmission rates [8-10]. However, guidelines vary and their recommendations are often based on expert opinion and evidence from observational studies.
INDICATIONS —
Cesarean birth is performed when the clinician and patient believe that abdominal birth is likely to provide a more favorable maternal and/or fetal outcome than vaginal birth. Thus, indications for cesarean birth fall into two general categories:
●Medically/obstetrically indicated
●On patient request (see "Cesarean birth on patient request")
Approximately 70 percent of cesarean births in the United States are primary (first) cesareans [11]. The three most common indications for primary cesarean birth in the United States account for almost 80 percent of these births [12]:
●Failure to progress during labor (35 percent)
●Nonreassuring fetal status (24 percent)
●Fetal malpresentation (19 percent)
Less common indications for primary cesarean birth include, but are not limited to:
●Abnormal placentation (eg, placenta previa, placenta accreta spectrum, vasa previa)
●Maternal infection with significant risk of perinatal transmission during vaginal birth
●Fetal bleeding diatheses
●Funic (cord) presentation or cord prolapse
●Suspected macrosomia (typically ≥5000 grams in patients without diabetes, ≥4500 grams in patients with diabetes)
●Mechanical obstruction to vaginal birth (eg, large obstructing fibroid, severely displaced pelvic fracture, severe fetal macrocephaly)
●Uterine rupture
●Prior extensive transmyometrial uterine surgery, such as some myomectomies and reconstructive surgeries for repair of congenital uterine anomalies
Although infrequent, cesarean birth is also indicated in patients who are at increased risk for complications/injury from cervical dilation, descent and expulsion of the fetus, or episiotomy. Some examples include patients with invasive cervical cancer, active perianal inflammatory bowel disease, or history of repair of a rectovaginal fistula or pelvic organ prolapse. (See "Cervical cancer in pregnancy" and "Fertility, pregnancy, and nursing in inflammatory bowel disease" and "Effect of pregnancy and childbirth on urinary incontinence and pelvic organ prolapse" and "Fecal and anal incontinence associated with pregnancy and childbirth: Counseling, evaluation, and management".)
Cesarean birth is not routinely indicated for low estimated fetal weight (see "Delivery of the low birth weight singleton cephalic fetus"), twin pregnancy with the first twin in cephalic presentation (see "Twin pregnancy: Labor and delivery"), and most congenital anomalies (refer to topic reviews on individual anomalies).
CONTRAINDICATIONS —
There are no absolute contraindications to cesarean birth. In contrast to other types of surgery, the risks and benefits of the procedure are considered as they apply to at least two patients (pregnant individual and at least one fetus). However, many pregnant individuals have a low tolerance for accepting any fetal risk from vaginal birth, irrespective of the maternal risks associated with cesarean birth [13,14].
PREOPERATIVE PLANNING
Patient education/consent — Good clinical practice involves counseling the patient about the procedure and the plan for their care before, during, and after the cesarean birth. A consent form for the procedure should be reviewed, including basic procedural information, risks, and benefits; all questions should be answered prior to signing. This information may diminish anxiety, help patients make well-informed choices regarding their care, and thereby enhance postoperative recovery. (See "Cesarean birth: Postoperative care, complications, and long-term sequelae", section on 'Complications' and "Informed consent in obstetrics".)
As part of patient education, implications for future pregnancies should be discussed. These issues are reviewed separately. (See "Cesarean birth: Postoperative care, complications, and long-term sequelae", section on 'Long-term risks' and "Cesarean birth: Postoperative care, complications, and long-term sequelae", section on 'Future pregnancy and delivery'.)
Using checklists — Checklists can be helpful for preoperative planning and are available from various organizations, such as the American College of Obstetricians and Gynecologists (ACOG) and Agency for Healthcare Research and Quality (AHRQ) [7].
Planning postpartum contraception — Postpartum contraception plans should be discussed during prenatal care, and decisions made well before the intrapartum period. (See "Contraception: Postpartum counseling and methods".)
For patients who are certain that they desire permanent contraception or who desire intrauterine contraception, the procedure or device placement can be performed at the time of cesarean birth. (See "Overview of female permanent contraception" and "Postpartum permanent contraception: Procedures", section on 'Following cesarean birth' and "Contraception: Postpartum counseling and methods", section on 'Issues related to postpartum IUD placement'.)
Scheduling
●Medically/obstetrically indicated cesarean births
•Medically/obstetrically indicated cesarean births are scheduled when clinically indicated, which may be preterm. If preterm birth (<37+0 weeks) or early term birth (37+0 to 38+6 weeks) is not indicated, there is consensus that the cesarean birth should not be scheduled before 39+0 weeks [15-17]. If the pregnancy is suboptimally dated, scheduling should be based at the appropriate clinical time with the best clinical estimate of gestational age used [18]. We caution against performing an early term cesarean (at 37 or 38 weeks of gestation) when the medical/obstetric indication for delivery is "soft," such as a history of a fetal, maternal, or obstetric complication in a previous pregnancy that has not recurred.
This approach is based on data from large, observational studies and randomized trials that consistently show that neonatal respiratory morbidity and/or composite neonatal morbidity is higher after scheduled (planned) cesarean birth without medical indication and decreases as gestational age increases from 37 to 40 weeks [19-27]. An example of the magnitude of these risks was provided by a study that evaluated maternal and neonatal outcomes according to completed week of gestation in over 23,000 repeat cesarean births performed before the onset of labor [28]. Rates of composite neonatal morbidity with elective cesarean birth by week of gestation were: 37 weeks (16.7 percent), 38 weeks (10.7 percent), 39 weeks (7.1 percent), 40 weeks (6.5 percent), 41 weeks (9.0 percent). Composite maternal morbidity was lowest at 39 weeks (0.9 percent). In addition, for the neonate, delivery at 39 and 40 weeks was associated with less risk of adverse neonatal outcome compared with pregnancy continuation (39 weeks: odds ratio [OR] 0.79, 95% CI 0.68-0.92; 40 weeks: OR 0.57 95% CI 0.43-0.75). The composite neonatal outcome included death, respiratory distress syndrome, transient tachypnea, necrotizing enterocolitis, mechanical ventilation, sepsis, hypoxic-ischemic encephalopathy, neonatal intensive care unit admission, and 5-minute Apgar ≤3.
●Planned repeat cesarean birth – Planned repeat cesarean births are scheduled based on the type of previous hysterotomy incision and reviewed separately. (See "Repeat cesarean birth", section on 'Timing'.)
●Cesarean birth on maternal request – Cesarean birth on patient request should not be scheduled before the 39th week of gestation. (See "Cesarean birth on patient request".)
Unscheduled cesareans — Compared with scheduled cesarean birth, intrapartum cesarean is associated with increased risks of postpartum hemorrhage, anesthetic complications from rapid administration of general anesthesia (if performed), and accidental injury to the fetus or abdominopelvic organs. Intrapartum cesarean births are sometimes classified by degree of urgency. Examples include:
●An immediate threat to life of the mother or fetus is present
●Signs of maternal or fetal compromise are present but are not immediately life threatening
●Delivery is needed, but there is no evidence of maternal or fetal compromise
Intrapartum cesarean birth is common, but reported rates vary widely. Although many risk prediction models exist, they do not accurately predict which patients in the overall obstetric population will undergo an intrapartum cesarean birth [29].
PREPROCEDURE MATERNAL PREPARATIONS
Perioperative management of chronic medications — Perioperative management of medications that the patient is taking regularly is similar to that for other surgical procedures, and discussed separately. (See "Perioperative medication management".)
Skin self-cleansing — We do not advise patients to use any particular product to cleanse their skin before cesarean, although preoperative protocols often ask patients to shower or bathe with soap (nonantimicrobial or antimicrobial) or an antiseptic agent the night before the day of surgery.
A placebo-controlled randomized trial of pregnant individuals undergoing cesarean birth failed to show benefit from preadmission application of chlorhexidine gluconate-impregnated cloths to six skin sites the night before and after a shower the morning of scheduled surgery [30]. Meta-analyses of randomized trials of preoperative bathing or showering with chlorhexidine or other products before a variety of other surgical procedures also have found no clear reduction in surgical site infection rates [31-34].
Skin preparation in the operating room is discussed below. (See 'Skin preparation' below.)
Oral intake — We encourage clear liquids for up to two hours before surgery and tell patients to avoid solids for six hours before surgery and fatty meals for eight hours before surgery. For patients without diabetes, some guidelines suggest consuming clear liquids that contain carbohydrates (eg, apple juice, Gatorade) [6]. Encouraging fluids up to two hours prior to surgery and carbohydrate loading (45 grams is suggested) are thought to reduce preoperative stress; maintain euvolemia, cardiac output, and delivery of oxygen and nutrients to the tissues; and minimize postoperative insulin resistance, which promote wound healing [35]. Oral intake is reviewed in detail separately. (See "Preoperative fasting in adults".)
Anesthesia consultation — As with any surgical procedure, patients undergoing cesarean birth should have a preoperative consultation with an anesthesiologist. Those whose procedure-related risks are above baseline should have a preadmission consultation, if possible. Characteristics that place the patient at increased risk may include, but are not limited to, those listed in the table (table 1).
The choice of regional or general anesthesia is influenced by factors such as the urgency of the procedure, maternal status and comorbid conditions, and physician and patient preferences. In general, neuraxial anesthesia is preferred, unless contraindicated. Issues related to anesthesia for cesarean birth, including choice of anesthesia and preanesthetic medications (eg, antacids, histamine H2 receptor antagonists), are discussed in detail separately. (See "Anesthesia for cesarean delivery".)
Laboratory testing — A baseline hemoglobin or hematocrit measurement is recommended for patients who are undergoing major surgery, such as cesarean birth, that is expected to result in significant blood loss. A value in the normal range obtained within one month of surgery probably does not need to be repeated preoperatively in uncomplicated pregnancies.
In the United States, The Joint Commission requires use of an evidence-based tool for determining maternal hemorrhage risk on admission to the labor and delivery unit [36]. Based on assessment of low, medium, or high risk of hemorrhage, blood is sent to the blood bank for holding in readiness, type and screen, or crossmatch, respectively. Methods of risk assessment and preparation for postpartum hemorrhage, a relatively common life-threatening obstetric emergency, are integral components of intrapartum care and reviewed separately. (See "Overview of postpartum hemorrhage", section on 'Institutional planning and preparation'.)
Other issues to consider
●Bowel preparation (oral and/or mechanical) is not beneficial and is not recommended [2,37].
●Surgery in patients with obesity presents additional challenges, which are discussed separately. (See "Cesarean birth: Overview of issues for patients with obesity".)
PROPHYLACTIC MEDICATIONS
Antibiotic prophylaxis and antiseptic preparation
Usual regimen — For all patients not already on antibiotics and undergoing cesarean birth, we administer:
●Cefazolin within the 60 minutes before making the skin incision [38-40]:
•<120 kg – 2 g intravenously (IV)
•≥120 kg – 3 g IV
●PLUS a single dose of azithromycin 500 mg IV for patients in labor or with ruptured membranes [41].
●PLUS antiseptic abdominal and vaginal cleansing preparation. (See 'Skin preparation' below and 'Vaginal preparation' below.)
A single dose of antibiotics was as effective as multiple doses in systematic reviews of randomized trials of patients undergoing cesarean birth [42,43]. However, a second dose of cefazolin is reasonable in patients with postpartum hemorrhage >1500 mL [39] and for the rare complicated cesarean birth that extends beyond four hours (or two half-lives of the drug) since the half-life of cefazolin is approximately 1.8 hours [38,44]. Although such redosing is the standard of care in other surgeries, there are no specific data for cesarean birth [45].
The American College of Obstetricians and Gynecologists (ACOG) recommends a single dose of a first-generation cephalosporin (eg, patients ≤80 kg or with a normal body mass index [BMI]: cefazolin 1 g IV, patients ≥80 kg or BMI ≥30 kg/m2: 2 or 3 g IV) [39].
Patients with penicillin allergy — These patients fall into two groups: those with previous serious reactions and those at low risk for a serious reaction. The risk of a penicillin-allergic patient reacting to a cephalosporin may be assessed based upon the results of penicillin skin testing (ideally performed prenatally), the clinical features of the penicillin reaction, and the time elapsed since the last reaction to penicillin (algorithm 1). (See "Allergy evaluation for immediate penicillin allergy: Skin test-based diagnostic strategies and cross-reactivity with other beta-lactam antibiotics" and "Penicillin allergy: Immediate reactions".)
●For patients with a history of a serious form of penicillin allergy, we suggest a single dose of combination therapy within the 60 minutes before making the skin incision [38-40]
•Clindamycin 900 mg IV
•PLUS gentamicin 5 mg/kg IV
•PLUS a single dose of azithromycin 500 mg IV for patients in labor or with ruptured membranes [41].
Serious forms of penicillin allergy include immediate reactions (ie, anaphylactic) (table 2), as well as several types of delayed reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis, drug rash eosinophilia systemic symptoms, drug-induced liver or other organ injury, and drug-induced cytopenias). In recent years, it has been noted that patients with type I IgE-mediated hypersensitivity reactions to penicillins, including anaphylaxis and rash, may safely receive cefazolin because it has a unique R1 side chain different from other cephalosporins (cefaclor, cefadroxil, cephalexin, cefprozil), which have R1 side chains structurally similar to penicillin [46,47]. This has prompted an emerging change in traditional recommendations and allowed expanded use of cefazolin in some patients who report penicillin allergy [48]. Cefazolin should not be used in those with a history of a severe, life-threatening, delayed hypersensitivity reaction, such as Steven-Johnson Syndrome. (See "Choice of antibiotics in penicillin-allergic hospitalized patients".)
When gentamicin is used for prophylaxis in combination with a parenteral antimicrobial with activity against anaerobic agents, we advise 4.5 to 5 mg/kg of gentamicin as a single dose as many studies support the safety and efficacy of this dose when used as a single dose for prophylaxis in patients without acute or chronic kidney disease. In addition, a trial of antibiotic prophylaxis in colorectal surgery reported that this dose may be more effective than multiple standard doses of 1.5 mg/kg during prolonged surgeries [49]. However, cesarean birth typically takes less than an hour; thus, a lower dose of gentamicin may be adequate; there are no comparative dosing trials in this population. Single daily dose gentamicin dosing does not appear to be associated with more neonatal nephrotoxicity or auditory toxicity than multiple daily doses [50].
●For patients at low risk of a serious immediate allergic reaction, we use the same regimen as in patients without a penicillin allergy. (See 'Usual regimen' above.)
Evidence
●Benefits (reduction of maternal infection) – In the absence of antimicrobial prophylaxis, patients undergoing cesarean birth have a 5- to 20-fold greater risk for infection compared with those who give birth vaginally [51]. The benefit of antibiotic prophylaxis before cesarean birth was illustrated in a systematic review of randomized trials that compared maternal outcomes with versus without use of prophylactic antibiotics and found that antibiotic prophylaxis reduced the risk of endometritis by approximately 60 percent in both antepartum and intrapartum cesarean births (95 trials, >15,000 participants) [51]. The risks of wound infection, urinary tract infection, and serious maternal infectious complications were also reduced. In a smaller systematic review that evaluated neonatal outcomes (12 trials, >5000 participants), nonstatistically significant reductions in neonatal sepsis (risk ratio [RR] 0.76, 95% CI 0.51-1.13) and neonatal infection with antimicrobial-resistant bacteria (RR 0.70, 95% CI 0.32-4.14) were found, and would be clinically important if proven true if more robust data become available [40].
Although the relative risk reduction in maternal infection is statistically significant and similar for both scheduled and intrapartum procedures, the absolute risk of maternal infection is quite low in antepartum cases: In a large observational study of such cases, postpartum endometritis occurred in 2 percent of patients with antibiotic prophylaxis versus 2.6 percent without antibiotic prophylaxis; wound infection occurred in 0.52 percent of patients with antibiotic prophylaxis versus 0.96 percent without antibiotic prophylaxis [52]. Thus, 1000 patients undergoing antepartum cesarean birth would receive antibiotics to prevent 6 cases of endometritis and 4.4 cases of abdominal wound infection.
●Drug choice and dose – Comparative trials do not provide strong evidence on which to base a recommendation for the optimal drug and dose. Based on expert opinion from infectious disease experts, we administer cefazolin, with dosing based on weight [38]. The higher dose for patients with obesity is based on pharmacokinetic data rather than surgical site infection (SSI) rates, and these data have been inconsistent [53-57]. Cefazolin has a longer half-life than ampicillin (1.8 versus 0.7 to 1.5 hours in adults with normal kidney function [58]), which is an advantage in long surgeries. In a 2021 systematic review of randomized trials, first- and second-generation cephalosporins (eg, cefazolin, cefoxitin) and broad-spectrum penicillins plus betalactamase inhibitors (eg, amoxicillin plus clavulanic acid, ampicillin plus sulbactam) appeared to be similarly effective for preventing postoperative maternal infection (endometritis, wound infection) after cesarean birth; use of adjunctive azithromycin to target Ureaplasma and Mycoplasma species was not evaluated [59].
Additional data from randomized trials support use of extended-spectrum antibiotic combinations (eg, cefazolin plus azithromycin, cefazolin plus metronidazole) for patients at high risk of post-cesarean infection [60]. In a seminal placebo-controlled multicenter randomized trial including over 2000 pregnant patients, administration of azithromycin 500 mg IV before skin incision in addition to preoperative cefazolin resulted in a 50 percent reduction in the composite outcome of endometritis, wound infection, or other infection (endometritis 3.8 versus 6.1 percent, wound infection 2.4 versus 6.6 percent; composite RR 0.51, 95% CI 0.38-0.68), without impacting the frequency of adverse neonatal outcomes [41]. Of note, only patients who had a cesarean birth during labor or at least four hours after rupture of membranes were included, so these data do not apply to other cesarean births (eg, antepartum cesarean births with intact membranes). Specific tests for Ureaplasma or Mycoplasma species were not routinely performed, thus it is not known whether coverage against Ureaplasma and Mycoplasma species provided by the extended antibiotic regimen accounted for the reduction in postoperative infection. Observational studies evaluating the use of azithromycin prophylaxis of prelabor cesarean births in patients with intact membranes have reported discordant results [61,62]. No adequately powered randomized trial has evaluated adding azithromycin to cefazolin in this setting. Therefore, we continue to only use cefazolin for prophylaxis in patients with intact membranes not in labor.
Special populations
●Patients already on antibiotics – There are no randomized trials assessing efficacy of antibiotic regimens in these clinical scenarios.
•Patients receiving GBS prophylaxis – When cesarean birth is performed in a patient in labor or with ruptured membranes receiving penicillin G for neonatal Group B Streptococcus (GBS) prophylaxis, we do not add a cephalosporin or switch to ampicillin for surgical prophylaxis, but we add a 500 mg dose of azithromycin for patients in labor or with ruptured membranes. Alternatively, some clinicians add a single dose of a narrow-spectrum antibiotic (eg, cefazolin) as well as a dose of azithromycin to the penicillin G protocol for GBS prophylaxis.
•Patients with chorioamnionitis – Ampicillin plus gentamicin is a common regimen for treatment of chorioamnionitis. For patients already on this regimen, we also administer either one dose of clindamycin 900 mg or metronidazole 500 mg before beginning the cesarean. We do not administer azithromycin to these patients, even if they are in labor or have ruptured membranes, but practice patterns vary. (See "Clinical chorioamnionitis", section on 'Cesarean birth'.)
Postpartum, it is reasonable to either continue ampicillin plus gentamicin or switch to ampicillin-sulbactam until the patient is afebrile for at least 24 hours. Bacteroides resistance to clindamycin is increasing; thus, in areas of high resistance, ampicillin-sulbactam is preferable. (See "Clinical chorioamnionitis", section on 'Postpartum care'.)
●Patients with nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) – Routine screening for MRSA is not indicated. Management of patients known to be colonized is discussed separately and may involve addition of a single dose of vancomycin. (See "Antimicrobial prophylaxis for prevention of surgical site infection in adults", section on 'Role of vancomycin'.)
Postpartum hemorrhage prophylaxis (tranexamic acid) — Prophylactic administration of tranexamic acid may be used to reduce the risk of postpartum hemorrhage, even in low-risk patients. The author of this topic often administers tranexamic acid before making the skin incision and then administers routine uterotonic drug prophylaxis (eg, oxytocin) after delivery of the newborn [63,64]. Delaying administration until after cord clamping was not effective in some randomized trials [65]. Evidence on the safety and efficacy of tranexamic acid prophylaxis is reviewed separately. (See "Prophylactic pharmacotherapy to reduce the risk of postpartum hemorrhage".)
Prevention of nausea and vomiting — Nausea with or without vomiting occurs commonly during cesarean with neuraxial anesthesia. Prophylaxis for intraoperative and postoperative nausea and vomiting is routine. (See "Anesthesia for cesarean delivery", section on 'Preventing nausea and vomiting'.)
Thromboembolism prophylaxis
Risk of VTE — The pooled incidence of venous thromboembolism (VTE: deep vein thrombosis and/or pulmonary embolism) after cesarean birth was 2.6 VTE per 1000 cesareans in a meta-analysis [66]. Thus, the absolute level of risk for clinically important events is low and similar to that seen in very low-risk surgical patients, in whom routine thromboprophylaxis is not recommended (other than early ambulation) (see "Prevention of venous thromboembolic disease in adult nonorthopedic surgical patients", section on 'Selecting thromboprophylaxis'). However, pulmonary embolism is a common cause of maternal mortality [67] and over 80 percent of fatal puerperal pulmonary embolisms occur after cesarean births [68]. (See "Cesarean birth: Postoperative care, complications, and long-term sequelae", section on 'Venous thromboembolism'.)
Our approach — The value of thromboprophylaxis for cesarean birth has not been studied in adequately powered randomized trials that have assessed and quantified both benefits (prevention of VTE and/or pulmonary embolism) and harms (wound or bleeding complications, including unplanned surgical procedures and blood transfusions) [69-72]. Observational studies of pregnant patients suggest that pneumatic compression devices, as well as graduated compression stockings, are safe and effective [73,74] (see "Prevention of venous thromboembolic disease in adult nonorthopedic surgical patients", section on 'Low VTE risk: Mechanical methods'). International guidelines for pharmacologic thromboprophylaxis after cesarean birth differ markedly in selection of patients because both the optimal threshold for initiating pharmacologic thromboprophylaxis and optimal duration of therapy are unclear [75]. Furthermore, no easy-to-use, validated tool is available for accurately determining absolute risk of postpartum VTE in an individual patient, although pilot studies of such tools have been published [76,77]. Clinical validation is difficult given the relatively low incidence of VTE.
Our approach, which is generally consistent with ACOG and Society for Maternal-Fetal Medicine (SMFM) recommendations, is described below [78-80].
Low-VTE-risk patients — We suggest mechanical thromboprophylaxis and early ambulation:
●Before beginning the cesarean birth, initiate mechanical thromboprophylaxis (intermittent pneumatic compression [IPC] is preferred) and continue it postoperatively.
●Encourage early and frequent ambulation postoperatively, as soon as eight hours after the cesarean birth.
●IPC may be removed while the patient is ambulating but should be replaced when they return to their bed or chair. IPC is discontinued at hospital discharge.
High-VTE-risk patients — We suggest both mechanical and pharmacologic thromboprophylaxis (table 3) and early ambulation:
●Before beginning the cesarean birth, initiate mechanical thromboprophylaxis (IPC is preferred) and continue it postoperatively at least until pharmacologic thromboprophylaxis has been started. We generally continue mechanical thromboprophylaxis until the patient is discharged to home as it may offer additive benefit to pharmacologic thromboprophylaxis.
●Pharmacologic prophylaxis with heparin is initiated 6 to 12 hours after cesarean birth in patients who received general anesthesia, but should be delayed in patients with excessive bleeding or significant risk of excessive bleeding.
If neuraxial anesthesia is used, the timing depends on several factors, including the time of placement of the needle/catheter, the time of removal of the epidural catheter (if used), whether low molecular weight heparin (LMWH) or unfractionated heparin is being administered, the dose (low, intermediate, or therapeutic), and whether placement was traumatic. Decision-making regarding the timing of postpartum thromboprophylaxis should consider the risk of bleeding related to surgery/postpartum hemorrhage and the risk of spinal epidural hematoma. We use the Society for Obstetric Anesthesia and Perinatology guidelines for anticoagulant timing, which are shown in the table (table 4) [81]. (See "Anticoagulation during pregnancy and postpartum: Agent selection and dosing", section on 'Postpartum and breastfeeding' and "Neuraxial anesthesia/analgesia techniques in the patient receiving anticoagulant or antiplatelet medication".)
●Encourage early and frequent ambulation postoperatively, as soon as eight hours after the cesarean birth.
Identifying high-VTE-risk patients — Criteria for selecting patients at high VTE risk are challenging as high-quality data are not available [82]. Most available risk-assessment models (RAMs) for VTE events have not been well-validated (eg, Padua, Caprini, Wells, Royal College of Obstetricians and Gynaecologists [RCOG]) in peripartum patients [83-85]. The RCOG has a detailed, complex RAM that uses a numerical scoring system for numerous preexisting, obstetric, and transient risk factors and advises LMWH for all patients undergoing intrapartum cesarean and for patients undergoing scheduled cesarean with additional risk factors [86]. The duration of thromboprophylaxis varies from 10 days to 6 weeks depending on the risk assessment score but is extended in the presence of persistent risk factors.
We consider any of the following reasonable criteria for mechanical plus pharmacologic thromboprophylaxis:
●Previous VTE.
●Any thrombophilia (inherited or acquired).
●BMI >35 kg/m2 (ie, class II obesity).
●None of the above but other risk factors for VTE – The type and number of other risk factors that meet the threshold for administering pharmacologic prophylaxis is decided by institutional protocols or on a case-by-case basis (table 5) [86-97]. A major consideration is the risk of VTE versus the risk of pharmacologic prophylaxis (wound hematoma) in each case.
Duration of anticoagulation — The duration of pharmacologic prophylaxis depends on the clinical setting:
●Previous VTE
•Before the index pregnancy – Treat for at least six weeks postpartum.
•During the index pregnancy – Treat for at least three months (this should include the remainder of pregnancy and at least six weeks postpartum).
●Inherited thrombophilia – Patients with high-risk thrombophilias may require life-long anticoagulation, while those with low-risk thrombophilias require anticoagulation for at least six weeks (table 6). (See "Inherited thrombophilias in pregnancy", section on 'Prevention of VTE'.)
●BMI >35 kg/m2 – Treat at least until the patient is ambulatory and longer (10 days to six weeks postpartum) depending on the type and presence of other risk factors.
●Other risk factors (eg, prolonged immobilization, active cancer) – These patients require an individualized approach. Patients who require prolonged anticoagulation can be switched to an oral agent (eg, warfarin [which can be used during lactation] or a direct oral anticoagulant [which should not be used during lactation]). (See "Heparin and LMW heparin: Dosing and adverse effects", section on 'Transitioning between anticoagulants'.)
(See "Anticoagulation during pregnancy and postpartum: Agent selection and dosing", section on 'Duration of postpartum anticoagulation' and "Selecting adult patients with lower extremity deep venous thrombosis and pulmonary embolism for indefinite anticoagulation" and "Antiphospholipid syndrome: Obstetric implications and management in pregnancy" and "Inherited thrombophilias in pregnancy" and "Venous thromboembolism in pregnancy and postpartum: Treatment".)
Thromboprophylaxis guidelines from major medical societies
●American College of Clinical Pharmacy (ACCP) guidelines for antithrombotic therapy and prevention of thrombosis in pregnancy [87,98]
●Royal College of Obstetricians and Gynaecologists (RCOG) [86]
●American College of Obstetricians and Gynecologists (ACOG) [78]
●Society for Maternal-Fetal Medicine (SMFM) [79]
PREOPERATIVE FETOPLACENTAL ASSESSMENT
Fetal heart rate monitoring — For patients waiting to undergo a scheduled cesarean birth, the value of continuous or intermittent fetal heart rate monitoring following admission to the labor and delivery unit is unclear; no randomized trials examining this issue have been performed [99]. At a minimum, the fetal heart rate should be documented upon admission, similar to other vital signs. If the patient has been undergoing antepartum fetal testing, it is reasonable to perform an admission nonstress test and discontinue monitoring if the tracing is reactive. If abdominal preparation for surgery is not performed shortly after anesthetic placement, it is appropriate to recheck the fetal heart rate during the delay.
For laboring patients, fetal heart rate monitoring should continue after transfer to the operating room, to the extent possible. External monitors are removed when the abdominal preparation is begun; internal monitors may be removed when the abdominal preparation is completed, although some surgeons may choose to continue monitoring until birth, especially if the incision to delivery interval may be prolonged because of adhesions or other factors.
Fetal presentation and placental location — An ultrasound for assessment of placental location and fetal presentation (or abdominal examination to assess fetal presentation) may be useful before surgery, but is not required. For example, it may help the surgeon avoid disturbing an anterior placenta or fibroid at hysterotomy, it confirms persistent nonvertex presentation in cases in which this is the indication for the cesarean, and it may help with planning extraction of a fetus in nonvertex presentation.
INTRAOPERATIVE CARE
Time-out — The time-out before making the incision is an established approach to risk reduction in the operating room. The procedure is reviewed in detail separately. (See "Patient safety in the operating room".)
Environment
Natural, gentle, or family-centered environment — The "natural," "gentle," or "family-centered" cesarean birth approach was developed to improve the birth experience of patients having uncomplicated cesarean births. It attempts to replicate features of vaginal birth as much as possible to make cesarean surgery more family friendly. Components of this approach may include [100,101]:
●Reduction of extraneous noise (eg, conversation among staff) and playing background music of the patient's choice during birth.
●Dimming lights, when safely possible.
●Using clear drapes or positioning the drapes to allow the parent(s) to watch the birth.
●Avoiding maternal sedation.
●Allowing a support person.
●Allowing the infant to be born by a combination of natural uterine expulsion and active physician assistance to mimic expulsion from the vagina.
●Allowing the umbilical cord to be cut by the support person.
●Freeing the mother's dominant hand/arm and chest/breasts from lines and monitors, when possible, so they can hold and nurse the newborn.
●Promoting skin-to-skin contact and nursing immediately after birth, for at least 30 minutes.
Family-centered cesarean is preferred whenever feasible (ie, routinely unless an emergency cesarean needs to be performed). It improves birth satisfaction and breastfeeding initiation and duration without increasing surgical morbidity [102].
Room temperature — Normothermia should be maintained during anesthesia and surgery. Patients receiving neuraxial anesthesia become hypothermic to a degree that is similar to those having general anesthesia.
A warm room temperature is also important for the newborn. The cesarean birth operating room temperature should be approximately 25°C (77°F) for preterm neonates ≤32 weeks, and 23°C (73°F) or 24°C (75°F) for all other neonates, to prevent neonatal hypothermia [103,104]. (See "Perioperative temperature management".)
Music — In patients undergoing a cesarean birth, music was associated with decreased intraoperative anxiety in a meta-analysis of randomized trials [105]. Therefore, we suggest asking patients their preference for having or not having music, and what kind of music they would like during the cesarean.
Noise level — Background noise levels in the operating room during cesarean birth should be at a level that allows for efficient and clear communication. This specific decibel level has yet to be defined [106].
Patient preparation
Bladder catheterization — Available evidence, although limited, does not support benefit from routine placement of an indwelling bladder catheter at cesarean birth [107,108]. As an alternative, patients at low risk of intraoperative complications can be asked to void shortly before entering the operating room. If subsequently required, an indwelling catheter can be inserted intraoperatively or postoperatively, and removed as soon as possible [109-112].
Nevertheless, many clinicians insert a urethral catheter at the start of the case to prevent bladder distention and thereby improve visualization during surgery and minimize the risk for bladder injury. The catheter is also useful for instilling dye if a cystotomy is suspected and for monitoring urine output. Potential harms include an increased risk of urinary tract infection, urethral pain, voiding difficulties after removal of the catheter, delayed ambulation, and longer hospital stay [108]. If inserted, the catheter should be removed soon after the end of the cesarean [113]. (See "Placement and management of urinary catheters in adults" and "Complications of urinary bladder catheters and preventive strategies".)
Hair removal — Meta-analyses of randomized trials in nonpregnant patients report no difference in the rate of surgical site infection (SSI) in those who had hair removed prior to surgery versus those who did not [114,115]. No randomized trials assessing this intervention specifically before cesarean birth have been performed.
If hair needs to be removed, it should be clipped rather than shaved as patients who are shaved are more likely to develop SSI. Use of a depilatory cream is also preferable to shaving. Clipping should be performed just before surgery. (See "Overview of control measures for prevention of surgical site infection in adults", section on 'Hair removal'.)
Skin preparation — We prepare the abdominal surgical site with a chlorhexidine-alcohol scrub before cesarean birth based on data from three randomized trials that reported a reduction in SSI or positive bacterial wound cultures compared with iodine-alcohol skin preparation; two trials were in patients undergoing cesarean birth [116,117] and the other in adults undergoing clean-contaminated surgery [118].
However, use of iodine-alcohol, povidone-iodine, or chlorhexidine soap is also reasonable [119]. Alcohol-based surgical prep solutions contain approximately 70 to 75 percent isopropyl alcohol and are flammable if not allowed to dry sufficiently before use of an ignition source; at least three minutes are required. Therefore, preparation with povidone-iodine or chlorhexidine soap (eg, Hibiclens) is advantageous when surgery cannot be delayed for three minutes, as these solutions are not flammable.
A 2020 meta-analysis of randomized trials evaluating skin preparation techniques concluded there was insufficient evidence overall for determining the most effective skin preparation technique for preventing post-cesarean SSI or for reducing other undesirable outcomes [120]. Of note, in a subanalysis, chlorhexidine-alcohol was more effective than povidone-iodine for reducing SSI (risk ratio [RR] 0.72, 95% CI 0.58-0.91, eight trials, 4323 patients), but the difference was attenuated when four trials at high risk of bias were removed. Guidance for intraoperative care in cesarean birth from the American College of Obstetricians and Gynecologists (ACOG) and the Enhanced Recovery After Surgery (ERAS) Society recommend use of an alcohol-based mixed solution, such as chlorhexidine-alcohol [3,39].
Vaginal preparation — For patients in labor and patients with ruptured membranes, the author of this topic performs a 4% chlorhexidine gluconate vaginal scrub with a sponge stick for 30 seconds to lower SSI risk, particularly endometritis. Povidone-iodine is a reasonable alternative but was less effective in reducing wound infection in one of the largest randomized trials comparing these two options [121]. Importantly, preparations with a high alcohol content (chlorhexidine gluconate with 70% alcohol used for skin preparation) should be avoided in the vagina because alcohol irritates mucous membranes [39].
●In a 2020 meta-analysis of 21 randomized trials of vaginal cleansing (povidone-iodine or chlorhexidine) versus placebo/no intervention before cesarean birth in over 7000 individuals, vaginal cleansing resulted in reductions in endometritis (3 versus 7.2 percent, RR 0.41, 95% CI 0.29-0.58), postoperative fever (RR 0.64, 95% CI 0.50-0.82), and wound infection (3.8 versus 6.1 percent, RR 0.62, 95% CI 0.50-0.77) [122]. In subgroup analysis, both iodine-based or chlorhexidine-based solutions were efficacious and patients in labor or with ruptured membranes before the cesarean derived the greatest absolute benefit. Neither cleansing agent resulted in adverse effects. While a subsequent randomized trial specifically comparing precesarean abdominal plus vaginal cleansing (povidone-iodine) in patients in labor, with rupture of membranes, or with cervical dilation >4 cm found no significant difference in postoperative infectious morbidity compared with abdominal cleansing alone (11.8 versus 11.5 percent; RR 1.0, 95% CI 0.7-1.6) [123], the body of evidence supports vaginal cleansing.
●A network meta-analysis of randomized trials confirmed that all antiseptic formulations (povidone-iodine, chlorhexidine, metronidazole gel, cetrimide) decreased the rate of endometritis compared with placebo (5.2 versus 9.1 percent, odds ratio [OR] 0.48, 95% CI 0.35-0.65); povidone-iodine had the highest probability of reducing the risk of endometritis, postoperative wound infections, and fever [124]. In the only trial that compared wound infection rates in patients assigned to chlorhexidine versus povidone-iodine before cesarean birth, the rate was lower in the chlorhexidine arm (0.6 versus 2 percent, OR 0.28, 95% CI 0.08-0.98) [121], which is the basis for the author's preference for chlorhexidine. Endometritis rates were low and similar in both arms (0.4 and 0.5 percent).
Nonadhesive drapes — The surgical site is draped with nonadhesive drapes.
●In a meta-analysis of two randomized trials in patients undergoing cesarean birth, nonadhesive drapes resulted in a statistically significant reduction in the rate of wound infection compared with adhesive drapes (10.7 versus 13.8 percent) [125].
Uterine displacement — The uterus is typically displaced at least 15 degrees to the left to reduce aortocaval compression (supine hypotensive syndrome), which can occur in the supine position when the uterus is at or above the umbilicus [126-130]. A foam or wood wedge, pillow, or rolled blanket may be used, or the table can be tilted, or the uterus can be manually displaced. However, a systematic review was not able to determine whether an optimal method for displacement exists or which maternal position is preferable [131]. (See "Anesthesia for cesarean delivery", section on 'Intraoperative positioning'.)
Other issues
Hemodynamic management — Preoperative and intraoperative euvolemia are desirable to avoid maternal and fetal complications of hypotension or fluid overload. The anesthesia team aims to maintain blood pressure within 10 to 20 percent of baseline blood pressure unless the patient has severe hypertension. Crystalloid solutions are used more commonly than colloid solutions. Glucose-free solutions should be used to prevent neonatal hypoglycemia. Vasopressors may be administered prophylactically and as needed. (See "Anesthesia for cesarean delivery", section on 'Hemodynamic management'.)
Cell salvage — Cell salvage may be useful, especially for cases in which high blood loss is expected, but more studies are needed to assess safety, benefits, cost, and optimal patient selection. (See "Surgical blood conservation: Intraoperative blood salvage".)
In a meta-analysis of five randomized trials comparing cell salvage to standard care in over 3000 patients undergoing cesarean birth with low to high risk for postpartum hemorrhage, cell salvage decreased the frequency of allogeneic blood transfusion (2.5 versus 7.4 percent; odds ratio [OR] 0.32, 95% CI 0.23-0.46) and reduced the postoperative fall in hemoglobin (mean difference 0.77, 95% CI -1.67 to 0.14), although the latter was not statistically significant [132]. Cell salvage was not harmful (ie, there was no increase in adverse events [transfusion reaction, longer length of hospital stay] and no cases of amniotic fluid embolism).
Supplemental oxygen — Healthy parturients do not require supplemental oxygen during neuraxial anesthesia. We administer supplemental oxygen via facemask or nasal cannulae to parturients with decreased oxygen saturation (eg, <95 percent). In cases with an abnormal fetal heart rate tracing, maternal oxygen administration will not correct fetal acidemia if the mother is not hypoxemic, and thus should not be used solely as a means of improving the fetal heart rate tracing. (See "Intrapartum category I, II, and III fetal heart rate tracings: Management", section on 'Interventions of no or uncertain benefit'.)
SOCIETY GUIDELINE LINKS —
Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Cesarean birth".)
INFORMATION FOR PATIENTS —
UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Basics topics (see "Patient education: Cesarean birth (The Basics)")
●Beyond the Basics topics (see "Patient education: C-section (cesarean birth) (Beyond the Basics)")
SUMMARY AND RECOMMENDATIONS
●Indications – Cesarean birth is performed when the clinician and patient believe that abdominal delivery is likely to provide a better maternal or fetal outcome than vaginal birth. A wide variety of conditions fulfill these criteria. (See 'Indications' above.)
●Scheduling – Medically/obstetrically indicated cesarean births are performed when clinically indicated. (See 'Scheduling' above.)
Planned primary cesarean birth and planned repeat cesarean birth at term in patients with a single prior low transverse hysterotomy should be performed in the 39th week of gestation rather than in the 37th or 38th week to minimize neonatal morbidity. In other patients with prior transmyometrial surgery, scheduling an earlier delivery may be indicated to minimize the risk that labor may begin spontaneously. Recommendations for these patients are reviewed separately. (See "Repeat cesarean birth", section on 'Timing' and "Uterine fibroids (leiomyomas): Issues in pregnancy", section on 'Patients with prior myomectomy'.)
●Preoperative planning and preparation – This includes informed consent, use of checklists, discussion of postpartum contraception, laboratory testing, blood availability as appropriate for the patient's risk of hemorrhage, and management of chronic medications and oral intake. (See 'Preoperative planning' above and 'Preprocedure maternal preparations' above.)
●Infection prophylaxis
•Systemic antibiotics – We recommend preincision antibiotic prophylaxis for all patients undergoing cesarean birth (Grade 1B).
-For patients undergoing scheduled cesarean birth with intact membranes, we suggest administering cefazolin (Grade 2C). We administer 2 g intravenously (IV) for patients <120 kg and 3 g IV for patients ≥120 kg within the 60 minutes before making the skin incision, in addition to antiseptic abdominal and vaginal preparation. For patients in labor or with ruptured membranes who are not already on antibiotics, we suggest adding azithromycin (Grade 2B). We administer a single dose of 500 mg IV. (See 'Usual regimen' above and 'Evidence' above and 'Skin preparation' above and 'Vaginal preparation' above.)
-For patients with a history of serious forms of penicillin allergy (algorithm 1), we substitute clindamycin and gentamicin for cefazolin. Patients at low risk of a serious immediate allergic reaction can receive cefazolin. If the cesarean birth is performed intrapartum or after rupture of membranes, we add a dose of azithromycin 500 mg IV. (See 'Patients with penicillin allergy' above.)
-For patients already receiving penicillin G for prophylaxis of neonatal Group B Streptococcus (GBS) infection, we do not add cefazolin or switch to ampicillin for surgical prophylaxis. If the cesarean birth is performed intrapartum or after rupture of membranes, we add a dose of azithromycin 500 mg IV. (See 'Special populations' above.)
-For patients receiving ampicillin and gentamicin for chorioamnionitis, we add either one dose of clindamycin 900 mg or metronidazole 500 mg before making the incision, and continue ampicillin and gentamicin or switch to ampicillin-sulbactam postpartum until the patient is afebrile for at least 24 hours. Bacteroides resistance to clindamycin is increasing; in areas of high resistance, ampicillin-sulbactam is preferable. We do not administer pre-incision prophylactic azithromycin in this setting. (See 'Special populations' above.)
•Other interventions – Most interventions for prevention of surgical site infection (SSI) are similar to those in general surgical patients (see 'Skin preparation' above and 'Nonadhesive drapes' above). For patients in labor and patients with ruptured membranes, we suggest vaginal preparation (Grade 2B). Either a povidone-iodine or chlorhexidine vaginal scrub is reasonable. (See 'Vaginal preparation' above.)
●Thromboprophylaxis
•For all patients undergoing cesarean birth, mechanical thromboprophylaxis is routine as in other low-risk surgical patients. All patients are also encouraged to ambulate early and frequently postoperatively. (See 'Thromboembolism prophylaxis' above and "Prevention of venous thromboembolic disease in adult nonorthopedic surgical patients".)
•For patients undergoing cesarean birth at highest risk of venous thromboembolism (VTE; eg, previous VTE, inherited or acquired thrombophilia), mechanical plus pharmacologic thromboprophylaxis is routine (see "Inherited thrombophilias in pregnancy" and "Antiphospholipid syndrome: Obstetric implications and management in pregnancy" and "Venous thromboembolism in pregnancy: Prevention"). We also suggest mechanical plus pharmacologic thromboprophylaxis for patients at increased but less high risk of VTE (Grade 2C). (See 'High-VTE-risk patients' above.)
Pharmacologic prophylaxis (table 3) is typically started 6 to 12 hours after surgery, in the absence of specific concerns about hemorrhage; however, the timing of placement of neuraxial anesthesia and the timing of removal of the epidural catheter also affect timing of pharmacologic prophylaxis (table 4). The duration of prophylaxis depends on the patient's specific risk status. (See 'High-VTE-risk patients' above.)
●Other chemoprophylaxis – Prophylaxis for intraoperative and postoperative nausea and vomiting is routine. Prophylactic use of tranexamic acid is an increasingly common approach for prophylaxis against postpartum hemorrhage, even in low-risk patients. The evidence for these interventions is reviewed separately. (See "Postoperative nausea and vomiting" and "Prophylactic pharmacotherapy to reduce the risk of postpartum hemorrhage", section on 'Tranexamic acid'.)
●Fetoplacental assessment – An ultrasound for assessment of placental location and fetal presentation (or abdominal examination to assess fetal presentation) may be useful before scheduled cesareans, but is not required in all patients. (See 'Preoperative fetoplacental assessment' above.)
●Intraoperative care – The uterus is typically displaced at least 15 degrees to the left to reduce aortocaval compression (supine hypotensive syndrome) (see 'Uterine displacement' above). An indwelling bladder catheter, hair removal, and supplemental oxygen are not necessary (see 'Bladder catheterization' above and 'Hair removal' above and 'Supplemental oxygen' above). Family-centered cesarean is preferred whenever feasible (see 'Environment' above). A time-out before making the incision is an established approach to risk reduction in the operating room. (See "Patient safety in the operating room".)
