Chapter 39. Sterilization
BS. Nguyễn Hồng Anh
Among women using contraception in the United States, 28 percent rely on either male or female sterilization (Kavanaugh, 2018). Tubal interruption or excision is suitable for those requesting sterilization and who clearly understand its permanence and its difficult and often unsuccessful reversal. Alternative contraceptive choices also should be presented. Ultimately, following provision of information, patient autonomy and her decision for sterilization should be respected (American College of Obstetricians and Gynecologists, 2017, 2019).
Female sterilization is usually accomplished by occlusion, excision, or division of the fallopian tubes. Puerperal sterilization procedures follow cesarean or vaginal delivery and approximately 7 percent of all live births in the United States (Moniz, 2017). Nonpuerperal tubal sterilization is done at a time unrelated to recent pregnancy and is also termed interval sterilization. More recently, consideration of total salpingectomy for sterilization and for ovarian cancer risk reduction is now recommended (p. 682).
PUERPERAL TUBAL STERILIZATION
■ Timing
Several days postpartum, the uterine fundus lies at the level of the umbilicus, and fallopian tubes are accessible directly beneath the abdominal wall. Moreover, abdominal laxity allows easy repositioning of the incision over each uterine cornu. On our service, puerperal tubal ligation is performed the morning after delivery by a surgical team designated solely to this role. This timing minimizes hospital stay but lowers the likelihood that postpartum hemorrhage would complicate recovery following surgery. The status of the newborn also can be better ascertained before surgery. In contrast, some prefer to perform sterilization immediately following delivery and use neuraxial analgesia already placed for labor. Designating these postpartum surgeries as nonelective can help lessen barriers. This is especially so for high-volume labor and delivery units, which typically prioritize their limited operating-room availability for intrapartum procedures (American College of Obstetricians and Gynecologists, 2021). From one large series, postpartum tubal ligation was a safe, reasonable option, regardless of body mass index (Byrne, 2020).
■ Method Selection
In general for postpartum sterilization, a midtubal segment of tube is excised, and the severed ends seal by fibrosis and peritoneal regrowth. Commonly used methods include the Parkland, Pomeroy, and modified Pomeroy techniques. Less often, Filshie clips are used, and evidence points to slightly decreased efficacy (Madari, 2011; Rodriquez, 2011, 2013). Also, in the absence of uterine or other pelvic disease, hysterectomy solely for sterilization is difficult to justify because of its significantly higher risk for surgical morbidity compared with tubal sterilization.
Most pelvic serous cancers are thought to originate from the distal fallopian tube (Erickson, 2013). Because of this, although currently theoretical, evidence suggests that bilateral salpingectomy may lower these ovarian cancer rates (Falconer, 2015; Lessard-Anderson, 2014). With this knowledge, the Society of Gynecologic Oncologists (Walker, 2015) and American College of Obstetricians and Gynecologists (2019b) recommend consideration of salpingectomy to lower these cancer risks. Specifically, for women at average risk of ovarian cancer, risk-reducing salpingectomy should be discussed and considered with abdominopelvic surgery, with hysterectomy, or in lieu of tubal ligation.
In the discussion of salpingectomy, several points are instructive. First, the lifetime risk for ovarian cancer approximates 1 percent (National Cancer Institute, 2019). Data from epidemiologic studies show that tubal interruption alone offers an approximate 30-percent decline in ovarian cancer rates (Rice, 2012; Sieh, 2013). Salpingectomy may reduce the risk by 42 to 78 percent (Gockley, 2018). However, no prospective studies of sufficient size or duration have yet been done to demonstrate the true risk and benefit ratio for women at low risk of ovarian cancer. Also, few data describe the effects on ovarian reserve from tubal blood supply disruption. In small studies comparing the two surgeries, no differences in antimüllerian hormone levels, which are a measure of ovarian reserve, were found (Findley, 2013; Ganer Herman, 2017). In other comparisons, total salpingectomy at cesarean delivery takes 5 to 10 minutes longer than partial salpingectomy (Ferrari, 2019; Powell, 2017). Blood loss rates are comparable or slightly higher but do not lead to higher transfusion rates or greater postsurgical declines in hematocrit values. Only a few small studies have evaluated salpingectomy following vaginal delivery (Danis, 2016; Powell, 2017).
■ Technique
Spinal analgesia is typically selected for cases scheduled on the first postpartum day. General anesthesia may be less desirable due to residual pregnancy-related aspiration risks (Bucklin, 2003). If done more proximate to delivery, the same epidural catheter used for labor analgesia can be used for sterilization analgesia. Generally, with thrombocytopenia-related conditions, platelet levels should be >70,000 for spinal blockade (Chap. 25, p. 478). The bladder is emptied before surgery to avoid its laceration. A full bladder can also push the fundus and tubes above the umbilicus and incision. Considered a clean case, antibiotic prophylaxis is not required. To begin, a small intraumbilical incision is ideal for several reasons. As noted, the fundus in most cases lies near the umbilicus. Second, the umbilicus usually remains the thinnest portion of the anterior abdominal wall and requires less subcutaneous dissection to reach the linea alba fascia. Third, an intraumbilical incision offers fascia with sufficient integrity to provide a closure with minimal risk for later incisional hernia. Last, incisions that follow the natural curve of the lower umbilical skin fold yield suitable cosmesis. A 2- to 3-cm transverse or vertical skin incision is usually sufficient for normal-weight women. For obese women, a 4- to 5-cm incision may be needed for adequate abdominal access. Beneath this incision, the subcutaneous tissue is bluntly separated to reach the linea alba fascia. For this, an Allis clamp can be opened and closed as downward pressure is exerted.
Similarly, the blades of two army-navy retractors both pulling in downward yet opposite directions can part the subcutaneous layer. Clearing this fatty tissue away from the fascia isolates the fascia for incision and for later closure without intervening fat, which may impede wound healing. The fascial incision may be transverse or vertical and follows the same orientation of the skin incision. For this, once the linea alba is reached, it is grasped with two Allis clamps—one placed on either side of the planned fascial incision (Fig. 39-1). The purchase of tissue with each clamp should be substantial and creates a small roll of fascia to be incised. Often, the peritoneum is incorporated simultaneously and entered. If not, the peritoneum is grasped with two hemostats and sharply cut. Others may prefer to bluntly enter with a single index finger. Notably, if the initial fascial incision is too small, it can be extended with curved Mayo scissors. Adequate exposure is critical, and army-navy or appendiceal retractors are suitable. For obese women, a slightly larger incision and narrow deeper retractors may be needed. If bowel or omentum is obstructing, trendelenburg position can help displace these cephalad. Digitally packing with a single, moist, fanned-out piece of surgical gauze also can be used, but a hemostat should always be attached to the distal end to avert its intraabdominal retention. At times, mechanically tilting the entire table to the opposite side of the tube being exposed also can assist tube isolation. The fallopian tube is identified and grasped at its midportion with a Babcock clamp. A second slightly more distal clamp grasps the tube, which is similarly lifted. This allows the fimbriated end to be seen. Such confirmation prevents confusing the round ligament for the fallopian tube. A common reason for sterilization failure is ligation of the wrong structure, typically the round ligament. If the tube is inadvertently dropped, it is mandatory to repeat this identification process. Surgical steps for ligation are outlined in Figures 39-2 and 39-3.
FIGURE 39-1 Fascia is grasped by two Allis clamps and elevated away from viscera beneath. Planned fascial incision is marked by dashed line. (Modified and reproduced with permission from Kho KA: Diagnostic and operative laparoscopy. In Yeomans ER, Hoffman BL, Gilstrap, III, et al [eds]: Cunningham and Gilstrap’s Operative Obstetrics, 3rd ed. New York, NY: McGraw Hill; 2017.)Sterilization 683
For total salpingectomy, the umbilical incision generally will need to be larger to allow an adequate view of the tube and mesosalpinx and to place clamps (Fig. 39-4). The entire mesosalpinx must be divided to free the fallopian tube. Thus, risks include bleeding from the often large, congested mesosalpingeal veins, control of which requires extension of the laparotomy incision or even an adnexectomy. Some prefer to use a bipolar electrosurgical coagulation device (LigaSure, ENSEAL), which seals and divides the mesosalpinx simultaneously. This may add speed but also expense.
After surgery, diet is given as tolerated, and walking is encouraged. Ileus is infrequent and should prompt concern for bowel injury, albeit rare. Most women have an uncomplicated course and are discharged on the first postoperative day.
NONPUERPERAL TUBAL STERILIZATION
These techniques and other modifications basically consist of (1) ligation and resection at laparotomy as described earlier for puerperal sterilization; (2) application of permanent rings, clips, or inserts to the fallopian tubes by laparoscopy or hysteroscopy; or (3) electrocoagulation of a tubal segment, usually through a laparoscope. A detailed description and illustration of these can be found in Williams Gynecology, 4th edition (Kho, 2020).
In the United States, a laparoscopic approach to interval tubal sterilization is the most common. The procedure is frequently performed in an ambulatory surgical setting under general anesthesia. In almost all cases, the patient can be discharged within several hours. Minilaparotomy using a 3-cm suprapubic incision also is popular, especially in resource-poor countries. Major morbidity is rare with either minilaparotomy or laparoscopy. Although not often used, the peritoneal cavity can be entered through the posterior vaginal fornix via colpotomy to perform tubal interruption.
LONG-TERM COMPLICATIONS
■ Contraceptive Failure
Pregnancy following sterilization is infrequent. The Collaborative Review of Sterilization (CRES) study followed 10,863 women
FIGURE 39-2 Parkland method. A. An avascular site in the mesosalpinx adjacent to the fallopian tube is perforated with a small hemostat. The jaws are opened to separate the fallopian tube from the adjacent mesosalpinx for approximately 2.5 cm. B. The isolated tubal portion is ligated proximally and distally with 0-chromic suture. The intervening segment of approximately 2 cm is excised, and the excision site is inspected for hemostasis. This method was designed to avoid the initial intimate proximity of the cut ends of the fallopian tube inherent with the Pomeroy procedure. (Reproduced with permission from Hoffman BL, Hamid CA, Corton MM: Surgeries for benign gynecologic conditions. In Hoffman BL, Schorge JO, Halvorson LM, et al: Williams Gynecology, 4th ed. New York, NY: McGraw Hill; 2020.)
FIGURE 39-3 Pomeroy method. During ligation of a midsegment tubal loop, plain catgut is used to ensure prompt absorption of the ligature and subsequent separation of the severed tubal ends. (Reproduced with permission from Hoffman BL, Hamid CA, Corton MM: Surgeries for benign gynecologic conditions. In Hoffman BL, Schorge JO, Halvorson LM, et al: Williams Gynecology, 4th ed. New York, NY: McGraw Hill; 2020.)
who had undergone tubal sterilization from 1978 through 1986 (Peterson, 1996). The cumulative failure rate for the various tubal procedures was 18.5 per 1000 or approximately 0.5 percent. The study found puerperal sterilization to be highly effective. The 5-year failure rate was 5 per 1000, and at 12 years, it was 7 per 1000.
Puerperal sterilization fails for two major reasons. First, surgical errors include transection of the round ligament or only partial transection of the tube. For this reason, both tubal segments are submitted for pathological confirmation. Second, a fistulous tract or spontaneous reanastomosis may form between the severed tubal stumps.
Approximately 30 percent of pregnancies that follow failed tubal sterilization are ectopic. This rate is 20 percent for those following a postpartum procedure (Peterson, 1996, 1997). Thus, any symptoms of pregnancy in a woman after tubal sterilization must be investigated to exclude ectopic pregnancy.
■ Other Effects
Women who have undergone tubal sterilization are highly unlikely to subsequently have salpingitis (Levgur, 2000). Most studies also find that rates of heavy menstrual or intermenstrual bleeding are not increased following the procedure (DeSteano, 1985; Peterson, 2000; Shy, 1992). Moreover, in the CRES study, Costello (2002) found that tubal ligation did not change sexual interest or pleasure in 80 percent of women. In most of the 20 percent of women who did report a change, positive effects were 10 to 15 times more likely.
Invariably, some women express regrets regarding sterilization, and this is especially true if it is performed at a younger age (Curtis, 2006; Kelekçi, 2005). In the CRES study, Jamieson (2002) reported that 7 percent of women who had undergone tubal ligation had regrets by 5 years. This is not limited to their own sterilization, because 6.1 percent of women whose husbands had undergone vasectomy had similar regrets.
■ Tubal Sterilization Reversal
No woman should undergo tubal sterilization believing that subsequent fertility is guaranteed either by surgery or by assisted reproductive technologies. Both approaches are technically difficult, expensive, and not always successful. In general, pregnancy rates after tubal reversal favor women with 7 cm of remaining tube, with age younger than 35 years, with a short time from antecedent sterilization, and with isthmic–isthmic repairs. With reanastomosis via laparotomy, rates of live births range from 44 to 82 percent (Deeux, 2011; Malacova, 2015). The rate of ectopic pregnancy is 2 to 10 percent after reanastomosis (American Society for Reproductive Medicine, 2015). With reanastomosis to reverse Essure sterilization, the subsequent live birth rates range from 0 to 27 percent (Fernandez, 2014; Monteith, 2014).
TRANSCERVICAL STERILIZATION
A transcervical approach to reach the tubal ostia can be used for sterilization. However, no methods using this approach are currently approved in the United States. Mechanical methods employ insertion of a device into the proximal fallopian tubes via hysteroscopy. Both the Essure system and the Adiana Permanent Contraception system have been removed from the U.S. market. Te Adiana is a cylindrical, nonabsorbent silicone elastomer matrix that once inserted stimulates tissue ingrowth to occlude the tubal lumen (Hologic, 2012).
The Essure Permanent Birth Control System is a long, slender, coiled, metallic tubal insert. Once placed, fibroblastic proliferation within the device similarly causes tubal occlusion. With this method, contraceptive failure rates range from <1 percent to 5 percent (Gariepy, 2014; Munro, 2014). Chronic pelvic pain after hysteroscopic sterilization may develop in 2 to 6 percent of those with Essure inserts ( Chudno, 2015; Kamencic, 2016; Yunker, 2015). Pain may stem
FIGURE 39-4 A. With salpingectomy, the mesosalpinx is sequentially clamped, cut, and ligated. B. At the cornu, clamps are placed across the fallopian tube and its adjacent mesosalpinx prior to tubal transection. (Reproduced with permission from Stuart GS: Puerperal sterilization. In Yeomans ER, Hoffman BL, Gilstrap, III, et al [eds]: Cunningham and Gilstrap’s Operative Obstetrics, 3rd ed. New York, NY: McGraw Hill; 2017.)
From tubal perforation, device migration, or the device itself (Adelman, 2014). For those desiring removal, proximal linear salpingostomy and device removal is feasible (Kho, 2020). Importantly, device removal is not curative in all symptomatic patients (Clark, 2017; Maassen, 2019). Other cited adverse events include abnormal bleeding and allergy or hypersensitivity reaction to its components (Al-Sa, 2013; Mao, 2015). Chemical agents may also be placed into the uterine cavity or tubal ostia to incite an inflammatory response to cause tubal occlusion. Used in lower-resource areas, one method employs an intrauterine device–type inserter to place quinacrine pellets into the uterine fundus. From randomized trials, pregnancy rates were 1 and 12 percent at 1 and 10 years, respectively (Sokal, 2008). The World Health Organization (2009) has recommended against quinacrine use because of carcinogenesis concerns. Evidence is contradictory, and some consider it a potential option for resource-poor countries (Lippes, 2015).
VASECTOMY
Currently, up to a half million men in the United States undergo vasectomy each year (Barone, 2006; Eisenberg, 2010). And, 5 percent of women rely on this method for contraception (Daniels, 2015). For sterilization, the vas deferens lumen is disrupted to block the passage of sperm from the testes (Fig. 39-5). Vasectomy is safer than female tubal sterilization because it is less invasive and is performed with local analgesia (American College of Obstetricians and Gynecologists, 2019a). In a review that compared the two, female tubal sterilization had a 20-fold higher complication rate and a 10- to 37-fold higher failure rate (Hendrix, 1999).
One disadvantage is that sterilization following vasectomy is not immediate. Sperm stored in the reproductive tract beyond the interrupted vas deferens takes approximately 3 months or 20 ejaculations for complete release. The American Urological Association recommends a postprocedural semen analysis at 8 to 16 weeks to document sterility ( Sharlip, 2012). Before azoospermia is documented, another form of contraception should be used. The failure rate for vasectomy during the first year is 9.4 per 1000 procedures but only 11.4 per 1000 at 2, 3, and 5 years (Jamieson, 2004). Failures result from unprotected intercourse too soon after ligation, incomplete vas deferens occlusion, or recanalization (Awsare, 2005; Deneux-Taraux, 2004). Reanastomosis of the vas deferens can be completed most effectively using microsurgical techniques. Conception rates following reversal are adversely affected by longer duration from vasectomy, poor sperm quality found at reversal, and type of reversal procedure required (American Society or Reproductive Medicine, 2008)
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