In 2016, the American Congress of Obstetricians and Gynecologists reaffirmed1 their 2012 opinion on the urgent nature of postpartum sterilization, “The immediate postpartum period following vaginal delivery or at the time of cesarean delivery is the ideal time to perform sterilization because of technical ease and convenience for the woman and physician.”2 Yet, fewer than half of women who request or plan for postpartum sterilization obtain the procedure, frequently for reasons that are familiar to labor and delivery staff:
- Too Sick: A 34-year-old G1P1 with sickle disease requests permanent sterilization after she delivers a healthy term neonate. Her pregnancy has been complicated by admissions for acute chest syndrome and pyelonephritis. Owing to concerns about anemia (postpartum hemoglobin 7.3 g/dL), the clinical team recommends she consider temporary contraception and plan for sterilization at a later date. Before discharge, she receives a Depo-Provera injection for contraception (medroxyprogesterone acetate; Pharmacia and UpJohn Co., LLC, New York, NY).
- Too Busy: A 24-year-old G4P4 requests postpartum sterilization following uncomplicated vaginal delivery. She had signed the federal sterilization consent form during her prenatal care. The clinical team keeps her nothing by mouth the night before planned discharge but is unable to fit her into that day’s busy operating room schedule. She is discharged with a prescription for oral contraceptives and a postpartum appointment to schedule an interval sterilization procedure.
- Too Soon: A 33-year-old G7P5 with late entry to prenatal care presents at 38 weeks of gestation with severe dyspnea, depressed cardiac function, and pulmonary edema. She has had 4 prior cesarean deliveries; the last was complicated by severe preeclampsia and peripartum cardiomyopathy. Before urgent repeat cesarean delivery, she requests tubal sterilization. The operative team informs her that she is ineligible for sterilization, because she signed the federal consent form only 16 days ago, and recommends intraoperative intrauterine device (IUD) placement instead.
- Too Late: A 30-year-old G3P3 has vaginal delivery on a Friday night with epidural analgesia. The epidural catheter is left in place, and she remains fasting while awaiting her postpartum sterilization; however, the labor floor is extremely busy, which delays her surgery. By midafternoon, she is very hungry, and with no anticipated operating room time, decides to eat. Eight hours later, she is appropriately fasted, but the obstetric and anesthesiology teams deem it inappropriate to perform an elective procedure at that hour, given the limited staffing and the presence of laboring women with category II fetal heart rate tracings on the unit. By Sunday morning, the uterus is no longer palpable at the umbilicus, and she is discharged with a plan to follow up at her 6-week appointment.
- Competing Risks: A 28-year-old G2P2 requests permanent sterilization after an uncomplicated, unmedicated vaginal delivery of a healthy neonate following a carefully timed induction of labor due to anticoagulation use in pregnancy. She has a history of venous thromboembolism related to factor V Leiden mutation homozygosity. The anesthesiologist insists on delaying surgery to allow for 6 hours of postpartum fasting, but the obstetrician plans to resume therapeutic anticoagulation 6 hours after delivery.
Anesthesiologists are routinely asked to provide anesthesia for postpartum tubal sterilization but may be unaware of related women’s health and social issues that impact family planning. This review examines these issues, including relative contraceptive effectiveness and safety, disparities in access to postpartum tubal sterilization, and consequences of failure to complete postpartum tubal sterilization as intended or desired. Armed with knowledge of these issues, anesthesiologists may better collaborate with women’s health care providers to advocate on patients’ behalf and to facilitate completion of postpartum tubal ligation (ppTL) when desired.
EFFECTIVENESS AND SAFETY OF POSTPARTUM STERILIZATION
Compared to other methods of postpartum contraception, postpartum sterilization is among the most effective and best tolerated. The Collaborative Review of Sterilization study, a prospective, multicenter, cohort study of 10,685 women,3 revealed a 10-year (1978–1987) cumulative failure rate for sterilization of 18.5 per 1000 for 6 methods used, and only 7.5 per 1000 for minilaparotomy partial salpingectomy. Most, but not all, failures occurred during the first 5 years after the procedure. A prospective randomized trial comparing 2 methods of minilaparotomy ppTL (titanium clip versus partial salpingectomy) conducted in 1985 to 1989 yielded a 2-year partial salpingectomy failure rate of 4 per 1000,4 mirroring Collaborative Review of Sterilization study results.
Postpartum tubal ligation is a safe surgical procedure. There are very limited data on the mortality risk of postpartum sterilization, because death attributable to this procedure is extremely rare. A large Swiss database of >5000 postpartum sterilization procedures reported zero deaths related to the procedure.5 Postoperative complications, such as intra-abdominal injury (0%–0.02%), hemorrhage (0.27%), febrile morbidity (0.06%), and thromboembolic events (0.04%) were also extremely rare, <0.5% overall.5 Poststerilization regret is the primary long-term complication, with a reported incidence in the United States ranging from 2 to 26 per 100 procedures.6–8 Risk factors for regret include young age, making the decision to undergo sterilization alone, insufficient counseling about the permanent nature of sterilization, subsequent changes in family structure (change of partner/marital status), and subsequent gynecologic or menstrual problems.7–9 Risks for regret that are specific to ppTL include an abrupt decision around the time of delivery, and ppTL performed during cesarean delivery, especially those performed for obstetric or medical reasons.6 Measures to prevent poststerilization regret include careful screening and counseling to mitigate these known risks.6
Alternative contraceptive options are highly reliable under conditions of optimal use. For example, contraceptive failure rates of available long-acting contraceptive methods, such as the copper T IUD, levonorgestrel IUD, and etonogestrel implant (0.8%, 0.2%, and 0.05%, respectively), are similar to surgical sterilization when continued at 1 year, but a large review of these methods revealed that after 1 year, only 78%, 80%, and 84% of couples continued these “long-acting” methods, respectively.10 Discontinuation is often related to user dissatisfaction with their chosen method due to side effects, such as changes in bleeding pattern or mood, which they attribute to the contraceptive. Discontinuation of contraceptive method leaves these patients vulnerable to unplanned pregnancy and places further burden on the health care system with need for subsequent visits for contraceptive counseling, costs of implementing new methods of contraception, and the issue of patient access to continued care toward the goal of preventing unintended pregnancy. Furthermore, as these long-acting reversible methods are approved for only 3 to 10 years of use, depending on device, reproductive-age women who desire permanent contraception may require >20 years of ongoing contraceptive care, with multiple device changes during this period. These additional burdens of health care costs and access are absent following surgical sterilization.
Women who leave the hospital without one of these methods in place are at risk of unintended pregnancy. In some cases, delayed contraception is not established as intended. For example, in a nonblinded trial, 112 women undergoing cesarean delivery and desiring an IUD were randomly assigned to intraoperative or interval IUD placement, 6 or more weeks postpartum. At 6 months, a larger proportion of women in the intraoperative placement group (83%) were using IUD than in the interval group (64%).11 Of the 56 women assigned to interval placement, 22 (39%) ultimately did not receive IUD, because they either failed to return for placement (14), were unable to have successful placement (3), or declined IUD at follow-up (5). Other women become pregnant before contraception is established. In a study of 1507 Australian primiparous women, 41% resumed vaginal sex within 6 weeks of delivery, 65% within 8 weeks, and 78% within 12 weeks.12 Although most nonlactating women will not ovulate until 6 weeks postpartum, ovulation can occur as early as 25 days after delivery.13 And while lactational amenorrhea is reliable if the woman is breast-feeding exclusively and the infant is younger than 6 months, many women do not breast-feed exclusively.14 In fact, according to the most recent Centers for Disease Control and Prevention data, only 18.8% of women in the United States report exclusive breast-feeding at 6 months.15 Of note, family leave policies in the United States, particularly in low-wage jobs, often do not have paid maternity leave, or provide <6 weeks of paid leave, which may serve as a significant barrier to returning for postpartum contraceptive care, particularly interval sterilization.
RACIAL, ETHNIC, AND SOCIOECONOMIC DISPARITIES IN ACCESS TO POSTPARTUM STERILIZATION SURGERY
Female sterilization is the most common contraceptive method among married American women, aged 15 to 44, and the second most common method overall (behind oral contraceptives), chosen by 27% of contraceptive-using women or 16.5% of all reproductive-age women in the United States.16,17 It is particularly popular among women of limited economic means, and for women without reliable long-term access to health insurance.18,19 Despite preference for tubal sterilization, supply does not meet demand in certain populations. Barriers to receiving desired sterilization surgery include inadequate hospital resources (operating room time, obstetrician and anesthesiologist availability); obstetrician reluctance due to concerns for patient regret in younger women, provision of obstetric care in a religiously affiliated hospital; fragmentation of intraconceptional, antepartum, intrapartum, and postpartum services and payment for those services; and incomplete, improperly completed, or unavailable original federal consent forms among Medicaid-insured women.2
To qualify for public funding, women (and men) must undergo the sterilization procedure not <30 days, and not >180 days after completing the Medicaid Title XIX Consent to Sterilization. A signed copy of the consent form must be physically available or verified at the time of the procedure. This requirement has significant effects on population health because almost half of all pregnant women in the United States (48% in 2010) receive their prenatal care from Medicaid.20 An exception is available in the event of emergency abdominal surgery or preterm delivery, when the 30-day wait period is reduced to 72 hours.21 Women with private insurance are not obligated to follow these consent requirements, which creates a 2-tiered system of access based on ability to pay.2,21,22
The federal informed consent requirements were originally established to protect vulnerable women from coercion. The performance of tubal sterilization increased significantly in the 1960s and 1970s when federally funded family-planning programs began subsidizing costs. In response to concerns of nonconsensual sterilization among minorities and the poor, the Department of Health, Education, and Welfare issued a standardized consent form for publicly funded sterilization procedures in 1976, and prohibited sterilization in persons under age 21 and those who were mentally incompetent or institutionalized.22,23 They also required written consent to be obtained at least 72 hours before the procedure. This mandatory wait period was extended to 30 days in 1978, and that policy remains in force today.23
Contemporary evidence suggests that these requirements, designed to avoid coercion, produce significant disparities in access to care.22–25 Only one-third to one-half of women desiring postpartum tubal ligation receive the procedure during their hospitalization for delivery. Four retrospective studies of 1363 parturients who desired ppTL reported procedure completion rates of 52%,21 56%,26 54%,27 and 31%.16 In the largest of these studies, 324 (46%) of 709 parturients who requested ppTL (predominantly African American and Latino, unemployed, unmarried, and insured by Medicaid) did not undergo the procedure.27 Among the reasons for failure to actualize the desired procedure, 121 women (37%) lacked valid Medicaid sterilization consent, while operating room unavailability was a barrier for 21 (6.5%).27
CONSEQUENCES OF FAILURE TO COMPLETE DESIRED POSTPARTUM TUBAL STERILIZATION—THE CASE FOR URGENCY
In 2011, an estimated 45% of pregnancies in the United States were unintended, most in women who were using contraception, and over half of which ended in termination.3 Unintended pregnancy rates are notably 5 times higher in poor women with incomes below the federal poverty line and are also higher in low-income and minority women.28 Unplanned pregnancy is the most significant complication of a failure to complete intended ppTL. A 1-year follow-up study of postpartum women examined 3 cohorts—those who requested and received ppTL, those who requested but did not receive the procedure, and a control group (those who did not request ppTL).16 Of 1460 women who delivered a liveborn singleton infant during a 6-month period, 429 requested ppTL. Of these, 296 (69%) received the procedure and 133 (31%) did not. Within 1 year of the index delivery, those requesting but failing to receive ppTL were twice as likely to get pregnant (46.7%) as those who did not request the procedure (22.3%), despite the fact that women in these 2 groups selected similar methods of postpartum contraception at hospital discharge.16
Borrero et al29 have calculated the cost of unintended pregnancies that resulted from unfulfilled sterilization requests due to Medicaid policy-related barriers. Assuming that 47% of ppTL requests go unfulfilled,27 that over half of these are due to Medicaid logistical barriers,27 and that nearly half of these women get pregnant within a year,16 they estimate that 113 potentially avoidable unintended pregnancies occur per 1000 women requesting a federally funded sterilization each year in the United States.29 In 2010, 136,853 Medicaid-funded postpartum sterilizations were performed in the United States. Given that only 53.3% of sterilization requests get fulfilled under the current federal policy, we estimate that 256,759 women likely requested the procedure.29 This equates to 29,013 potentially avoidable unintended pregnancies in the United States per year, at a total cost of $371 million (29,013 × $12,774, the average cost of a Medicaid-covered birth29). This represents a costly public financial burden. However, these are simply reimbursements for maternity care. In addition, the US Department of Agriculture has estimated that the average cost to raise a middle-class child born in 2015 up to age 18 is approximately $285,000.30 The disproportionate incidence of unplanned pregnancy among minorities and economically disadvantaged women, and those who have not completed high school, further accentuates and perpetuates societal inequity.
Unintended childbirth imposes significant health risks and costs for the woman, her children, and society.2 Maternal mortality in 2015 was estimated as 14/100,000 live births in the United States by the UN Maternal Mortality Estimation Inter-Agency Group,31 and was thought to be even higher by the Global Burden of Disease study at 26.4/100,000.32 Estimates of the global maternal mortality ratio for 2015 ranged from 195 to 216 per 100,000 worldwide.32–34 Severe maternal morbidity, as defined by an algorithm endorsed by the Centers for Disease Control and Prevention,35 was 129 per 10,000 delivery hospitalizations in the United States in 2008 to 2009.36 Importantly, significant racial and ethnic disparities exist with regard to maternal mortality and severe morbidity and affect non-Hispanic African American women most severely.37,38 Pregnancy also places women with serious medical comorbidities at higher risk for adverse outcomes. Unfortunately, these are the very populations with the highest risk of being denied their desired ppTL due to the multitude of reasons discussed above.
Unintended pregnancy has also been associated with poor-quality relationships between mother and child,39,40 higher rates of developmental delay,40 and adverse effects on maternal mental health.41 Additionally, these estimates ignore complications of rapid repeat pregnancy. An interpregnancy interval <18 months increases the risk of preterm birth, low birth weight, and small for gestational age infants, with higher rates of neonatal death as well if the interval is less than a year.42,43
TIMING OF POSTPARTUM STERILIZATION—OPTIMIZING EFFECTIVENESS AND SAFETY
Given the safety and effectiveness of ppTL, the high rate of unintended pregnancy and associated consequences when the desired procedure goes unfulfilled, and the narrow window for completing the procedure, the American College of Obstetricians and Gynecologists deems postpartum sterilization to be an urgent surgical procedure.2 Not to be confused with the cesarean urgency classification system by Lucas et al,44 ppTL is an add-on procedure that must be accomplished within a limited time window to reduce risk of serious long-term health consequences if not performed. This time window generally encompasses the duration of a woman’s postpartum stay following vaginal delivery. Barring maternal complications following delivery, ppTL may be considered soon after delivery, at the time of cesarean delivery, or during the postpartum hospitalization stay following vaginal delivery.17 Obstetricians may defer performing the procedure due to complications such as postpartum hemorrhage, hemodynamic instability, morbid obesity, and infection.2,6 There is evidence to suggest that partial salpingectomy via minilaparotomy can be safely performed up to 6 days postpartum 45; however, the majority of health insurance plans in the United States cover routine postpartum stays up to 48 hours following uncomplicated vaginal delivery. After 7 days postpartum, the infraumbilical incision used for ppTL may no longer be a reliable entry to access the rapidly involuting uterus,46 and interval procedure would become necessary. In some cases, uterine involution occurs more rapidly.
Normal postpartum physiologic changes should be considered. Maternal cardiac output peaks during the first hour after delivery, but there is no evidence that this affects anesthetic risk or management, unless the patient is at risk for heart failure and/or pulmonary edema. Alterations in airway anatomy, which may make tracheal intubation more difficult, occur during the course of pregnancy and are further exacerbated by labor.47 Maternal complications, such as large estimated blood loss, maternal infection or sepsis, or hemodynamic instability, may influence anesthetic management and warrant delaying surgery.2 The procedure has been safely completed in parturients with preeclampsia absent severe hemodynamic abnormalities.48,49
Despite lack of evidence to suggest that one anesthetic technique is superior to others, neuraxial anesthesia has been recommended over general anesthesia, presumably to reduce risks of pulmonary aspiration of gastric contents and difficult/failed intubation.50 Fasting guidelines similar to those of general surgical patients (no solid food within 6–8 hours) are recommended.50 However, these guidelines do not address immediate ppTL and potential presence of stomach contents owing to delayed gastric emptying associated with severe labor pain and/or opioid labor analgesics. Gastric emptying may remain delayed 2 hours after delivery51,52 and appears to return to normal within 18 hours of delivery.53,54 The stomach cannot be assumed to be empty immediately after delivery if painful labor, with or without neuraxial opioids, commenced soon after oral intake.55,56 Given evolving evidence56 and less restrictive policies regarding oral intake during labor,57 a coordinated postpartum preoperative fasting plan should be considered. It may be reasonable to permit clear liquid intake after delivery to satiate thirst and prolong time that women are willing to wait when there are delays due to competing workload and operating room inavailability. Standardized training in performing a bedside ultrasound examination of the gastric antrum in pregnant women has yielded good diagnostic accuracy and interrater reliability and may prove to be a helpful method of assessment.58,59
Administering local anesthetics through indwelling epidural catheters that have provided effective analgesia for labor and delivery produces satisfactory anesthesia for ppTL but with imperfect reliability.60–62 Success rates exceed 90% when epidural catheters are dosed within 4 hours of delivery, while success rates have ranged from 67% to 90% after 4 hours.60–62 Extending the anesthetic block before the labor analgesic sensory block regresses after delivery may promote greater success.60 For those without preexisting epidural analgesia, spinal anesthesia using hyperbaric local anesthetics with or without opioids has been reported.63–68 Adding 100 μg morphine sulfate to hyperbaric lidocaine 60 mg and fentanyl 10 μg was shown to significantly reduce static and dynamic postoperative incisional pain, as well as cramping pain during the first 24 hours, compared to lidocaine and fentanyl alone.63 Other investigators have reported effective spinal anesthesia when combining 50 to 100 μg morphine with hyperbaric bupivacaine64,65,68 and 10 μg fentanyl with hyperbaric ropivacaine.66 Some have recommended spinal anesthesia even in parturients with indwelling epidural catheters to avoid less than perfect epidural reactivation rates and minimize time delays and costs.61 Finally, in a series of 90 parturients undergoing minilaparotomy ppTL at least 8 hours following vaginal delivery, general anesthesia with isoflurane and nitrous oxide using a Proseal laryngeal mask airway (LMA®; Teleflex Medical Europe Ltd, Athlone, Ireland) produced satisfactory conditions.69 The choice of anesthetic technique may depend on timing relative to delivery. Immediately following delivery, epidural extension or spinal anesthesia with a reliable technique may be most appropriate, given aspiration risk. For ppTL closer to hospital discharge, when aspiration risk is low, spinal anesthesia or general anesthesia will facilitate rapid recovery and hospital discharge. In either case, multimodal analgesia, including nonsteroidal anti-inflammatory drugs, is recommended,68,70 particularly for women scheduled for immediate postoperative discharge.
THE ANESTHESIOLOGIST’S OPPORTUNITY TO LEAD SYSTEMS CHANGES FOR EQUITABLE AND SAFE CARE
Obstetric anesthesiologists have made valued contributions to many facets of peripartum care. We propose extending attention and advocacy to this important aspect of maternal care. With greater understanding of barriers, consequences, and disparities around postpartum sterilization, the obstetric anesthesiologist can better collaborate with other maternal care providers to promote quality outcomes.
- Quality Measurement: Failure to perform postpartum sterilization meets the criteria that define a medical error, ie, failure to complete a planned action as intended.71 Considered as such, using common improvement processes—identifying contributing factors,21,27 devising and implementing interventions, and assessing improvement71—should reduce the incidence of this omission error. Establishing consensus among interprofessional team members and institutional leadership regarding the procedure’s importance, both to individual patients and to public health, is an important first step toward improving routine performance of this procedure on short notice.2 Concurrent care for other parturients on a busy labor and delivery unit inevitably affects availability of resources needed to complete this procedure. Resource constraints include physical space (operating room, extended recovery time), personnel (surgeon, anesthesiologist, nurses, scrub tech),2,27 and may be dynamic based on concurrent obstetric patient activity, varying based on time of day and week. Tracking the failure rate and conducting event analyses to identify specific contributing factors might yield solutions, such as increased staffing overall or on a contingency basis, consideration of operating sites beside the labor and delivery suite, identifying or creating operating room time to accept add-on tubal sterilization procedures, and system improvements to ensure availability of required completed consent forms.
- Allocation of Resources: Anesthesia staffing has been cited as a limiting factor in completing intended ppTL, even in high-volume obstetric centers.72 When demands for anesthesia services exceed capacity or resources, our typical response is to seek creative solutions in the short term and work to adjust and augment resources in the long term. Postpartum sterilization should activate the same problem-solving response. Unfortunately, the recent update of Practice Guidelines for Obstetric Anesthesia is silent on urgency and instead deprioritizes the procedure relative to other obstetric care, “If a postpartum tubal ligation is to be performed before the patient is discharged from the hospital, do not attempt the procedure at a time when it might compromise other aspects of patient care on the labor and delivery unit,”50 despite citing American Congress of Obstetricians and Gynecologists recommendations on urgency owing to consequences of a missed procedure. Although the authoring task force examined maternal complications in deriving guidelines, their scope was limited to the immediate short term, overlooking strong published evidence regarding long-term complications and consequences, “…the literature is insufficient to evaluate the impact of the timing of a postpartum tubal ligation on maternal outcome.”50
- Leadership, Advocacy, Policy: In recent years, anesthesiologists have increasingly teamed up with hospital providers and administrators in areas such as quality improvement, rapid response teams, sedation safety, comprehensive pain services, and the perioperative surgical home concept. In keeping with our increasingly broadening health care leadership roles, should we not join other women’s health advocates in promoting policies promoting equitable reproductive health and health care, and ensuring that such care is available to all women, regardless of socioeconomic differences?
Unplanned repeat pregnancy is a significant problem in the United States, with costs to the patient, society, and the health care system. Postpartum tubal sterilization is a safe and effective means of reducing unplanned repeat pregnancy. Among most patients who receive epidural analgesia for labor and delivery, epidural anesthesia can be extended for ppTL with a high rate of success, especially if done in a timely manner after delivery. Alternatively, spinal and general anesthesia have been shown to be effective and safe. However, responsibility does not end with safe anesthetic care. As peripartum and perioperative physicians advancing population health, anesthesiologists should engage more fully with parturients and their obstetric providers to reduce the current rate of failure to achieve desired postpartum tubal sterilization.
The authors are indebted to David H. Chestnut, MD, for his critical review of this manuscript and suggestions.
Name: Michael G. Richardson, MD.
Contribution: This author helped write the manuscript.
Name: Sarah J. Hall, MD, PhD.
Contribution: This author helped write the manuscript.
Name: Lisa C. Zuckerwise, MD.
Contribution: This author helped write the manuscript.
This manuscript was handled by: Jill M. Mhyre, MD.
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