Sterilization: Introduction. Female Sterilization. Puerperal Tubal Sterilization

Transcription

1 Print Close Window Note: Large images and tables on this page may necessitate printing in landscape mode. Copyright The McGraw-Hill Companies. All rights reserved. Williams Obstetrics > Section VI. The Puerperium > Chapter 33. Sterilization > Sterilization: Introduction Surgical sterilization has become the most popular form of contraception. The volume of sterilization procedures cannot be tracked accurately in the United States because most interval tubal sterilizations and vasectomies are performed in ambulatory centers. Westhoff and Davis (2000), however, citing data from the National Survey of Family Growth, estimate that about 700,000 tubal sterilizations are performed annually. Unfortunately, there are still excessive federal rules and regulations that discourage voluntary sterilization among financially underprivileged women. Several important multicenter studies of voluntary sterilization have been performed by investigators of the U.S. Collaborative Review of Sterilization (CREST) and the Centers for Disease Control and Prevention. Many of their observations are subsequently described. Female Sterilization Female sterilization is the contraceptive method of choice for 28 percent of couples in the United States (American College of Obstetricians and Gynecologists, 2003). It is usually accomplished by occlusion or division of the fallopian tubes. This can be performed at any time, but at least half of tubal sterilization procedures are performed in conjunction with cesarean or vaginal delivery (MacKay and associates, 2001). Nonpuerperal tubal sterilization is usually accomplished via laparoscopy in an outpatient surgical center. Puerperal Tubal Sterilization The oviducts are accessible at the umbilicus directly beneath the abdominal wall for several days after delivery. Thus, puerperal tubal sterilization is technically simple, and hospitalization need not be prolonged. Some practitioners prefer to perform sterilization immediately following delivery (Bucklin and Smith, 1999), although others wait for 12 to 24 hours. At Parkland and the University of Alabama Hospitals, puerperal tubal ligation is (1 of 20)9/10/2008 2:16:41 PM

2 performed in the obstetrical surgical suite the morning after delivery. This minimizes the hospital stay but allows the likelihood of postpartum hemorrhage to diminish. In addition, the status of the newborn can be better ascertained. The first tubal sterilization reported in the United States, performed 120 years ago, consisted of a silk ligature placed around the tubes about 1 inch from their uterine attachment after a cesarean delivery (Lungren, 1881). It soon was apparent that ligation without tubal resection had an unacceptably high failure rate, and a variety of techniques are now used to disrupt tubal patency. Irving Procedure This procedure is the most difficult to perform but the least likely to fail. The cut oviduct is separated from the mesosalpinx sufficiently to free a medial segment of tube (Fig. 33 1A). The freed distal stump of the proximal tubal segment is buried within a tunnel created in the myometrium posteriorly, and the proximal end of the distal tubal segment is buried within the mesosalpinx. Figure (2 of 20)9/10/2008 2:16:41 PM

3 Techniques for tubal sterilization. A. Irving procedure: the medial cut end of the oviduct is buried in the myometrium posteriorly, and the distal cut end is buried in the mesosalpinx. B. Pomeroy procedure: a loop of oviduct is ligated, and the knuckle of tube above the ligature is excised. Pomeroy Procedure This is the simplest method of dividing the tube (Fig. 33 1B). Plain catgut is used to ligate the knuckle of tube to ensure prompt absorption of the ligature and subsequent separation of the severed tubal ends. Even so, ectopic pregnancy in the distal segment can occur (Berker and colleagues, 2002). Parkland Procedure This procedure, shown in Figure 33 2, was developed in the 1960s. It was designed to avoid the initial intimate approximation of the cut ends of the oviduct inherent with the Pomeroy procedure. Figure (3 of 20)9/10/2008 2:16:41 PM

4 (4 of 20)9/10/2008 2:16:41 PM

5 Parkland tubal ligation: The avascular mesosalpinx is opened by blunt dissection. A 2-cm midsegment of tube is ligated with 0-chromic suture and divided between the sutures. Surgical Technique A small infraumbilical incision is made. The oviduct is identified by grasping its midportion with a Babcock clamp, and the distal fimbria is identified. This prevents confusing the round ligament with the midportion of the oviduct. Whenever the oviduct is inadvertently dropped, it is mandatory to repeat this identification procedure. An avascular site in the mesosalpinx adjacent to the oviduct is then perforated with a small hemostat, and the jaws are opened to separate the oviduct from the adjacent mesosalpinx for about 2.5 cm (see Fig. 33 2). The freed oviduct is ligated proximally and distally with 0-chromic suture, and the intervening segment of about 2 cm is excised and inspected for hemostasis. Both segments are submitted for histological confirmation. During four decades, the failure rate has been less than 1 in 400 procedures. Other Procedures The Madlenertechnique and the Kroener fimbriectomy for tubal sterilization are rarely used today because of high failure rates (Pati and Cullins, 2000). In most cases, failures are due to recanalization of the proximal portion of the tube. Failure Rates Puerperal sterilization fails for two major reasons. 1. Surgical errors, which include transection of the round ligament instead of the oviduct or partial transection of the oviduct. 2. Formation of a fistulous tract between the severed tubal stumps or spontaneous reanastomosis. In their first report, investigators from the CREST study described follow-up of 10,863 women who had undergone tubal sterilization from 1978 through The failure rates for various procedures are summarized in Figure It is readily apparent that puerperal sterilization is highly effective, with a short- and long-term failure rate that is better than most interval procedures. Some clinicians have reported an increased failure rate for sterilization at the time of cesarean delivery; however, we have identified no such differences with the technique of tubal sterilization used at Parkland Hospital (see Fig (5 of 20)9/10/2008 2:16:41 PM

6 2). Figure Data from the U.S. Collaborative Review of Sterilization (CREST) shows the cumulative probability of pregnancy per 1000 procedures for five methods of tubal sterilization. (Data from Peterson and colleagues, 1996.) Nonpuerperal (Interval) Tubal Sterilization Techniques for nonpuerperal tubal sterilization, including modifications, basically consist of: 1. Ligation and resection at laparotomy, as described earlier for puerperal sterilization. 2. The application of a variety of permanent rings or clips to the fallopian tubes, usually by laparoscopy. 3. Electrocoagulation of a segment of the tubes, again usually through a laparoscope. (6 of 20)9/10/2008 2:16:41 PM

7 Surgical Approaches A number of approaches and techniques may be used to perform nonpuerperal tubal sterilization. In developed countries, laparoscopic techniques are most often used. In the United States, laparoscopic tubal ligation is the leading method of female sterilization (American College of Obstetricians and Gynecologists, 2003). The procedure is frequently performed in an ambulatory surgical setting under general anesthesia with tracheal intubation. In almost all cases, the woman can be discharged several hours later. The actual disruption of tubal continuity is accomplished using loops, clips, and electrocauterization with or without transection of the tube. Because electrocauterization destroys a large segment of tube, surgical reversal is usually difficult and often not possible. "Minilaparotomy" using a 3-cm suprapubic incision is also popular, especially in resourcepoor countries (Kulier and colleagues, 2002). The peritoneal cavity can also be entered through the posterior vaginal fornix colpotomy or culdotomy to perform tubal interruption. This approach is not commonly used today. Major morbidity is rare with either minilaparotomy or laparoscopy. In the study by Kulier and associates (2002), minor morbidity was twice as common in women who had minilaparotomies. Laparoscopic Methods of Tubal Interruption A number of techniques or devices can be used to accomplish tubal sterilization via laparoscopy. Details of these have been provided by a number of reviews (Gilstrap and associates, 2002; Pati and Cullins, 2000). Electrocoagulation is used for destruction of a segment of tube and can be accomplished with either unipolar or bipolar electrical current. Although unipolar electrocoagulation has the lowest long-term failure rate (see Fig. 33 3), it also has the highest serious complication rate. For this reason, bipolar coagulation is favored by most clinicians (American College of Obstetricians and Gynecologists, 2003). Mechanical methods of tubal occlusion can be accomplished with a silicone rubber band such as the Falope Ring and the Tubal Ring; the spring-loaded Hulka-Clemens Clip (also (7 of 20)9/10/2008 2:16:41 PM

8 known as the Wolf Clip); or the silicone-lined titanium Filshie Clip. Sokal and co-workers (2000) compared the Tubal Ring and Filshie Clip in a randomized trial of 2746 women. They reported similar rates of safety and a 1-year pregnancy rate of 1.7 per 1000 women. All these methods have favorable long-term success rates (see Fig. 33 3). When done via laparoscopy, these procedures are technically more difficult, and they have significantly higher failure rates before experience is gained (Peterson and colleagues, 2001). Operative Complications Principal hazards are anesthetic complications, inadvertent injury of adjacent structures, the rare occurrence of pulmonary embolism, and sterilization failure with subsequent intrauterine or ectopic pregnancy (see Chap. 10). Because of improved safety with anesthetic and laparoscopic techniques, the case-fatality rates for tubal sterilization have diminished appreciably over the past 2 decades. For example, from 1977 to 1981, Peterson and co-workers (1983) estimated the case-fatality frequency to be 8 per 100,000 procedures. Fifteen years later, Hatcher and colleagues (1998) reported mortality rates of approximately 1.5 per 100,000 for laparoscopic sterilizations. Using the CREST database, Jamieson and co-workers (2000) reported an overall complication rate of 0.9 to 1.6 per 100 laparoscopic interval sterilization procedures. Unintended laparotomy was done in about 1 per 100 procedures. Failure Rates The reasons for interval tubal failures are not always apparent, but some are: 1. Surgical errors likely account for 30 to 50 percent of cases. 2. An occlusion method failure may be due to fistula formation, especially with electrocautery procedures. Faulty clips may not be occlusive enough, or the fallopian tube may spontaneously undergo reanastomosis. 3. Equipment failure, such as a defective electrical current for the electrocautery, may be a causative factor. 4. The woman was already pregnant at the time of surgery a so-called luteal phase pregnancy. As shown in Figure 33 3, some sterilization methods have lower failure rates than others. Even with the same procedure, there are variations in failure rate. For example, when (8 of 20)9/10/2008 2:16:41 PM

9 fewer than three tubal sites are coagulated, the five-year cumulative probability of pregnancy is about 12 per 1000 procedures. This compares with only 3 per 1000 if three or more sites are coagulated (Peterson and associates, 1999). The lifetime increased cumulative failure rates over time are supportive that failures after 1 year are not likely due to technical errors. Soderstrom (1985) found that most sterilization failures were not preventable. The American College of Obstetricians and Gynecologists (1996) concluded that "pregnancies after sterilization may occur without any technical errors." Long-Term Complications In addition to the 15-year cumulative pregnancy rates shown in Figure 33 3, there are other long-term adverse effects. Ectopic Pregnancy Approximately half of the pregnancies that follow a failed electrocoagulation procedure were ectopic, compared with only 10 percent following failure of a ring, clip, or tubal resection method (Hatcher and colleagues, 1990; Hendrix and associates, 1999). Any symptoms of pregnancy in a woman after tubal sterilization must be investigated, and an ectopic pregnancy must be excluded. Diagnosis and management are discussed in detail in Chapter 10. Posttubal Ligation Syndrome In 1951, Williams and colleagues described their 22-year experiences with long-term follow-up in women who had undergone tubal ligation. They reported an excessive incidence of menorrhagia and intermenstrual bleeding, a condition that later became known as posttubal ligation syndrome. Subsequently, a similar incidence of menstrual dysfunction was reported in women whose husbands had undergone vasectomy (DeStefano and colleagues, 1985; Shy and associates, 1992). Thus, debate over the very existence of a unique syndrome has persisted. Observations from the CREST study are very informative concerning these issues. Peterson and colleagues (2000) compared long-term outcomes of 9514 women who had undergone tubal sterilization with a cohort of 573 women whose partners had undergone vasectomy. They found that both groups had similar risks for menorrhagia, intermenstrual (9 of 20)9/10/2008 2:16:41 PM

10 bleeding, and dysmenorrhea. In fact, they found that women who had undergone sterilization had decreased duration and volume of menstrual flow as well as less dysmenorrhea. There was, however, an increased incidence of cycle irregularity in the sterilized women. The cause of these findings remains an enigma, although Harlow and coworkers (2002) reported no significant change in serum levels of follicle-stimulating hormone, luteinizing hormone, and estradiol. Timonen and co-workers (2002) reported a transient increase in follicular phase serum estradiol levels that normalized by 12 months. Other Effects Whether the incidence of subsequent hysterectomy is increased in women who have undergone tubal sterilization is controversial (Mall and colleagues, 2002; Pati and Cullins, 2000). In a CREST follow-up study, Hillis and associates (1997) reported that 17 percent of women undergoing tubal sterilization also underwent hysterectomy in the subsequent 14 years. Although the investigators did not compare this incidence with a cohort control, the indications were similar to those for nonsterilized women undergoing hysterectomy. Westhoff and Davis (2000) concluded that tubal sterilization likely protects against ovarian cancer. They found no differences in the incidence of breast cancer. According to Holt and colleagues (2003), the incidence of functional ovarian cysts is increased almost twofold following tubal sterilization. Levgur and Duvivier (2000) reported that women who had undergone tubal sterilization were highly unlikely to have subsequent salpingitis. Less objective but important psychological sequelae of sterilization have also been evaluated. In the CREST study, Costello and colleagues (2002) found that tubal ligation did not change sexual interest or pleasure in 80 percent of women. In the majority of the 20 percent of women who did report a change, positive effects were 10 to 15 times more likely to occur. Invariably, a number of women express regrets about sterilization. In the CREST study, Jamieson and co-workers (2002) reported that by 5 years, 7 percent of women who had undergone tubal ligation had regrets. This is not limited to their own sterilization, because 6.1 percent of women whose husbands had undergone vasectomy had similar regrets. Reversal of Tubal Sterilization (10 of 20)9/10/2008 2:16:41 PM

11 No woman should undergo tubal sterilization believing that subsequent fertility is guaranteed by either surgery or assisted reproductive techniques. These latter procedures are technically difficult, expensive, and not always successful. Success rates vary greatly depending on the age of the woman, the amount of tube remaining, and the technology used. Van Voorhis (2000) reviewed a number of reports and found that pregnancy rates varied from 45 to 90 percent with surgical reversals. For example, pregnancy rates as high as 80 percent have been reported for tubal reanastomosis (Cha and associates, 2001). When neosalpingostomy is done for fimbriectomy reversal, however, successful pregnancies occur in only 30 percent of women (Tourgeman and co-workers, 2001). Almost 10 percent of women who undergo reversal of tubal sterilization have an ectopic pregnancy. Reversal procedures can be done by laparoscopy or laparotomy, and pregnancy rates are similar with either method (Cha and colleagues, 2001). In a cost-effectiveness study from Canada, Hawkins and associates (2002) found laparoscopy to have lower costs than laparotomy. Hysterectomy For the woman who desires no more children, hysterectomy has many theoretical advantages. In the absence of uterine or other pelvic disease, however, hysterectomy solely for sterilization at the time of cesarean delivery, early in the puerperium, or even remote from pregnancy is difficult to justify. Transcervical Sterilization Sterilization has been performed by using hysteroscopy to visualize the tubal ostia and obliterating them with a variety of compounds or devices. Intratubal Chemical Methods Several compounds are being investigated as useful in tubal sterilization (Ballagh, 2003). Liquid silicone is injected transcervically into the tubes, where it hardens, forming silicone plugs. Repeat procedures are necessary in 20 percent of women, however, and continued tubal patency is common. Tubal injections with the adhesive methylcyanoacrylate cause inflammation, necrosis, and fibrosis. Insertion of quinacrine pellets in more than 100,000 women in other countries has also been used to achieve tubal occlusion. Few well-done studies concerning its efficacy are available, but advantages include minimal (11 of 20)9/10/2008 2:16:41 PM

12 complications and low cost. Randic and colleagues (2001) reported cumulative pregnancy rates by 8 years of more than 6 per 100. Because of concerns about carcinogenesis based on a study of 30,000 Vietnamese women, the World Health Organization recommended halting usage of quinacrine (Lippes, 2002). In addition, erythromycin placed tubally to incite inflammation has been investigated, but it has an unacceptably high one-year failure rate of 36 percent (Bairagy and Mullick, 2004). Intratubal Devices Tubes can be occluded by hysteroscopic insertion of some type of mechanical device into the proximal tube. Several of these devices have been evaluated. One of these, Essure, was approved by the Food and Drug Administration in November, This device is a microinsert that has a stainless steel inner coil enclosed in polyester fibers and an expandable outer coil of Nitinol a nickel and titanium alloy used in coronary artery stents. The outer coil expands after placement allowing the fiber to also expand, and as tissue grows within the fiber, tubal occlusion results. Preliminary results with this device and others have been encouraging (Association of Reproductive Health Professionals, 2002). In one study, Cooper and co-workers (2003) used intravenous sedation or paracervical block to insert Essure hysteroscopically. These investigators succeeded in proper insertion in 464 of 507 women (92 percent). None of these women had pregnancies by 9620 woman-months. In a similar study, Kerin and colleagues (2001) reported that 97 percent of women with the device in place after 2 years expressed a satisfaction level of very good to excellent. Essure use has two major drawbacks: the high cost of the device itself (almost $1000) and the necessity of hysterosalpingography at 3 months to ensure tubal blockage. (12 of 20)9/10/2008 2:16:41 PM

13 Male Sterilization Nearly a half million men in the United States undergo vasectomy each year (Magnani and colleagues, 1999). Through a small incision in the scrotum, the lumen of the vas deferens is disrupted to block the passage of sperm from the testes (Fig. 33 4). With local analgesia, the procedure is usually performed within 20 minutes. Figure Anatomy of male reproductive system, showing procedure for vasectomy. In a review, Hendrix and colleagues (1999) found that, compared with vasectomy, female tubal sterilization has a 20-fold increased complication rate, a 10- to 37-fold failure rate, and a 3-fold increased cost. Similarly, in Dallas in 2003, total charges for a vasectomy were $800 compared with almost $6000 for an outpatient laparoscopic tubal ligation. (13 of 20)9/10/2008 2:16:41 PM

14 A disadvantage of vasectomy is that sterility is not immediate. Complete expulsion of sperm stored in the reproductive tract beyond the interrupted vas deferens takes about 3 months or 20 ejaculations (American College of Obstetricians and Gynecologists, 1996). Although most protocols dictate that semen should be analyzed until two consecutive sperm counts are zero, Bradshaw and colleagues (2001) reported that only one azoospermic semen analysis is sufficient evidence of sterility. During the period before azoospermia is documented, another form of contraception must 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 and colleagues, 2004). Failures result from unprotected intercourse too soon after ligation, incomplete occlusion of the vas deferens, or recanalization. A phenomenon termed transient sperm reappearance usually is not associated with pregnancy. Haldar and co-workers (2000) described temporary low sperm counts in 20 of 2250 men who had been documented to have azoospermia following vasectomy. Of the 20, the count was less than 10,000/mL, and in the 14 retested one month later, azoospermia was again confirmed. They concluded that spermatozoa present in the distal vas deferens are slowly released, or that microchannels form with sperm granulomas. Restoration of Fertility Success after vasectomy reversal depends on several factors. Fibrosis increases with time (Raleigh and colleagues, 2004). A review of several reports suggests that odds for success are about 50 percent, with somewhat higher rates following microsurgical reanastomosis. Long-Term Effects Other than regrets, long-term consequences are rare (Amundsen and Ramakrishnan, 2004). After vasectomy, antibodies directed at spermatozoa can frequently be identified. Concern was raised about the possibility that the immune response might cause harmful systemic changes. Despite this, studies have not identified an increase in cardiovascular disease, circulating immune complexes, or damage to retinal blood vessels (Giovannucci and colleagues, 1992; Goldacre and co-workers, 1983). Subsequently, Manson and associates (1999) provided data on 1159 physicians from the U.S. Physicians' Health (14 of 20)9/10/2008 2:16:41 PM

15 Study. In a 15-year follow-up, there was no difference in the incidence of myocardial infarction or stroke in men with or without vasectomy. On the basis of their review, Schwingl and Guess (2000) also concluded that vasectomy is not followed by accelerated atherogenesis. There is no convincing evidence of an increased incidence of testicular cancer following vasectomy (Giovannucci and colleagues, 1992). Earlier studies found no evidence to associate development of prostatic carcinoma after vasectomy (Giovannucci and associates, 1993a, 1993b; Hayes and co-workers, 1993). This changed, however, when Lesko and colleagues (1999) compared follow-up results in 1216 vasectomized men and 1400 controls. They reported an almost twofold risk of prostatic cancer in men younger than 55 years of age, but not in older men. Following this, a population-based Danish cohort study found that prostatic cancer was not increased (Lynge, 2002). These findings indicate, at worst, a weak association that may be explicable by greater scrutiny of men who have undergone vasectomy (Grönberg, 2003). References American College of Obstetricians and Gynecologists: Benefits and risks of sterilization. Practice Bulletin No. 46, September, 2003 American College of Obstetricians and Gynecologists: Sterilization. ACOG Technical Bulletin No. 222, April, 1996 Amundsen GA, Ramakrishnan K: Vasectomy: A "seminal" analysis. South Med J 97:54, 2004 [PMID: ] [Full Text] Association of Reproductive Health Professionals: Clinical proceedings. Clinical update on transcervical sterilization. Washington, DC, 2002 Bairagy NR, Mullick BC: Use of erythromycin for nonsurgical female sterilization in West Bengal, India: A study of 790 cases. Contraception 69:47, 2004 [PMID: ] [Full Text] Ballagh SA: Sterilization in the office: The concept now is a reality. Contracept Technol Rep BB #S0315, February (15 of 20)9/10/2008 2:16:41 PM

16 Berker B, Kabukcu C, Dokmeci F: Tubal pregnancy after Pomeroy sterilization. Arch Gynecol Obstet 266:56, 2002 [PMID: ] [Full Text] Bradshaw HD, Rosario DJ, James MJ, et al: Review of current practice to establish success after vasectomy. Br J Surg 88:290, 2001 [PMID: ] [Full Text] Bucklin BA, Smith CV: Postpartum tubal ligation: Safety, timing and other implications for anesthesia. Anesth Analg 89:1269, 1999 [PMID: ] [Full Text] Cha SH, Lee MH, Kim JH, et al: Fertility outcome after tubal anastomosis by laparoscopy and laparotomy. J Am Assoc Gynecol Laparosc 8:348, 2001 [PMID: ] [Full Text] Cooper JM, Carignan CS, Cher D, et al: Microinsert nonincisional hysteroscopic sterilization. Obstet Gynecol 102:59, 2003 [PMID: ] [Full Text] Costello C, Hillis S, Marchbanks P, et al: The effect of interval tubal sterilization on sexual interest and pleasure. Obstet Gynecol 100:3, 2002 DeStefano F, Perlman JA, Peterson HB, et al: Long term risk of menstrual disturbances after tubal sterilization. Am J Obstet Gynecol 152:835, 1985 [PMID: ] [Full Text] Gilstrap LC, Cunningham FG, Van Dorsten P (eds): Obstetric hysterectomy. In Operative Obstetrics, 2nd ed. New York, McGraw-Hill, 2002 Giovannucci E, Ascherio A, Rimm EB, et al: A prospective study of vasectomy and prostate cancer in U.S. men. JAMA 269:876, 1993a Giovannucci E, Tosteson TD, Speizer FE, et al: A long-term study of mortality in men who have undergone vasectomy. N Engl J Med 326:1392, 1992 [PMID: ] [Full Text] Giovannucci E, Tosteson TD, Speizer FE, et al: A retrospective cohort study of vasectomy and prostate cancer in U.S. men. JAMA 269:878, 1993b Goldacre JM, Holford TR, Vessey MP: Cardiovascular disease and vasectomy. N Engl J Med 308:805, 1983 [PMID: ] [Full Text] Grönberg H: Prostate cancer epidemiology. Lancet 361:859, 2003 [PMID: ] [Full Text] (16 of 20)9/10/2008 2:16:41 PM

17 Haldar N, Cranston D, Turner E, et al: How reliable is a vasectomy? Long-term follow-up of vasectomised men. Lancet 356:43, 2000 [PMID: ] [Full Text] Harlow BL, Missmer S, Cramer D, et al: Does tubal sterilization influence the subsequent risk of menorrhagia or dysmenorrhea? Fertil Steril 77:4, 2002 Hatcher RA, Stewart F, Trussell J, et al: Contraceptive Technology, 15th ed. New York, Irvington, 1990, pp 391, 403, 416 Hatcher RA, Trussell J, Stewart F, et al: Contraceptive Technology, 17th ed. New York, Ardent Media, 1998, p 548 Hawkins J, Dube D, Kaplow M, et al: Cost analysis of tubal anastomosis by laparoscopy and by laparotomy. J Am Assoc Gynecol Laparosc 9:120, 2002 [PMID: ] [Full Text] Hayes RB, Pottern CM, Greenberg R, et al: Vasectomy and prostate cancer in US blacks and whites. Am J Epidemiol 137:263, 1993 [PMID: ] [Full Text] Hendrix NW, Chauhan SP, Morrison JC: Sterilization and its consequences. Obstet Gynecol Surv 54:766, 1999 [PMID: ] [Full Text] Hillis SD, Marchbanks PA, Tylor LR, et al: Tubal sterilization and long-term risk of hysterectomy: Findings from the United States Collaborative Review of Sterilization. Obstet Gynecol 89:609, 1997 [PMID: ] [Full Text] Holt VL, Cushing-Haugen KL, Daling JR: Oral contraceptives, tubal sterilization, and functional ovarian cyst risk. Obstet Gynecol 102:252, 2003 [PMID: ] [Full Text] Jamieson DJ, Costello C, Trussell J, et al: The risk of pregnancy after vasectomy. Obstet Gynecol 103:848, 2004 [PMID: ] [Full Text] Jamieson DJ, Hillis SD, Duerr A, et al: Complications of interval laparoscopic tubal sterilization: Findings from the United States Collaborative Review of Sterilization. Obstet Gynecol 96:997, 2000 [PMID: ] [Full Text] (17 of 20)9/10/2008 2:16:41 PM

18 Jamieson DJ, Kaufman SC, Costello C, et al: A comparison of women's regret after vasectomy versus tubal sterilization. Obstet Gynecol 99:1073, 2002 [PMID: ] [Full Text] Kerin JF, Carignan CS, Cher D: The safety and effectiveness of a new hysteroscopic method for permanent birth control: Results of the first Essure pbc clinical study. Aust N Z J Obstet Gynaecol 41:364, 2001 [PMID: ] [Full Text] Kulier R, Boulvain M, Walker D, et al: Minilaparotomy and endoscopic techniques for tubal sterilization. Cochrane Database Syst Rev 2002(3):CD Lesko SM, Louik C, Vezina R, et al: Vasectomy and prostate cancer. J Urol 161:1848, 1999 [PMID: ] [Full Text] Levgur M, Duvivier R: Pelvic inflammatory disease after tubal sterilization: A review. Obstet Gynecol Surv 55:41, 2000 [PMID: ] [Full Text] Lippes J: Quinacrine sterilization: The imperative need for clinical trials. Fertil Steril 77:1106, 2002 [PMID: ] [Full Text] Lungren SS: A case of cesarean twice. Am J Obstet Dis Women Child 14:78, 1881 Lynge E: Prostate cancer is not increased in men with vasectomy in Denmark. J Urol 168:488, 2002 [PMID: ] [Full Text] MacKay AP, Kieke BA, Koonin LM, et al: Tubal sterilization in the United States, Fam Plann Perspect 33:161, 2001 [PMID: ] [Full Text] Magnani RJ, Haws JM, Morgan GT, et al: Vasectomy in the United States, 1991 and Am J Public Health 89:92, 1999 [PMID: ] [Full Text] Mall A, Shirk G, Van Voorhis BJ: Previous tubal ligation is a risk factor for hysterectomy after rollerball endometrial ablation. Obstet Gynecol 100:659, 2002 [PMID: ] [Full Text] Manson JE, Ridker PM, Spelsberg A, et al: Vasectomy and subsequent cardiovascular disease in US physicians. Contraception 59:181, 1999 [PMID: ] [Full Text] (18 of 20)9/10/2008 2:16:41 PM

19 Pati S, Cullins V: Female sterilization: Evidence. Obstet Gynecol Clin North Am 27:859, 2000 [PMID: ] [Full Text] Peterson HB, DeStefano F, Rubin GL, et al: Deaths attributed to tubal sterilization in the United States, 1977 to Am J Obstet Gynecol 146:131, 1983 [PMID: ] [Full Text] Peterson HB, Jeng G, Folger SG, et al: The risk of menstrual abnormalities after tubal sterilization. N Engl J Med 343:1681, 2000 [PMID: ] [Full Text] Peterson HB, Xia Z, Hughes JM, et al: The risk of pregnancy after tubal sterilization: Findings from the U.S. Collaborative Review of Sterilization. Am J Obstet Gynecol 174:1161, 1996 [PMID: ] [Full Text] Peterson HB, Xia Z, Wilcox LS, et al: Pregnancy after tubal sterilization with bipolar electrocoagulation. U.S. Collaborative Review of Sterilization Working Group. Obstet Gynecol 94:163, 1999 [PMID: ] [Full Text] Peterson HB, Xia Z, Wilcox LS, et al: Pregnancy after tubal sterilization with silicone rubber band and spring clip application. Obstet Gynecol 97:205, 2001 [PMID: ] [Full Text] Raleigh D, O'Donnell L, Southwick GJ, et al: Stereological analysis of the human testis after vasectomy indicates impairment of spermatogenic efficiency with increasing obstructive interval. Fertil Steril 81:1595, 2004 [PMID: ] [Full Text] Randic L, Haller H, Sojat S: Nonsurgical female sterilization: Comparison of intrauterine application of quinacrine alone or in combination with ibuprofen. Fertil Steril 75:830, 2001 [PMID: ] [Full Text] Schwingl PJ, Guess HA: Safety and effectiveness of vasectomy. Fertil Steril 73:923, 2000 [PMID: ] [Full Text] Shy KK, Stergachis A, Grothaus LG, et al: Tubal sterilization and risk of subsequent hospital admission for menstrual disorders. Am J Obstet Gynecol 166:1698, 1992 [PMID: ] [Full Text] (19 of 20)9/10/2008 2:16:41 PM

20 Soderstrom RM: Sterilization failures and their causes. Am J Obstet Gynecol 152:395, 1985 [PMID: ] [Full Text] Sokal D, Gates D, Amatya R, et al: Two randomized controlled trials comparing the Tubal Ring and Filshie Clip for tubal sterilization. Fertil Steril 74:3, 2000 Timonen S, Tuominin J, Irjala K, et al: Ovarian function and regulation of the hypothalamic-pituitary-ovarian axis after tubal sterilization. J Reprod Med 47:131, 2002 [PMID: ] [Full Text] Tourgeman DE, Bhaumik M, Cooke GC, et al: Pregnancy rates following fimbriectomy reversal via neosalpingostomy: A 10-year retrospective analysis. Fertil Steril 76:1041, 2001 [PMID: ] [Full Text] Van Voorhis BJ: Comparison of tubal ligation reversal procedures. Clin Obstet Gynecol 43:641, 2000 Westhoff C, Davis A: Tubal sterilization: Focus on the U.S. experience. Fertil Steril 73:913, 2000 [PMID: ] [Full Text] Williams EL, Jones HE, Merrill RE: Subsequent course of patients sterilized by tubal ligation. Am J Obstet Gynecol 61:423, 1951 [PMID: ] [Full Text] Copyright The McGraw-Hill Companies. All rights reserved. Privacy Notice. Any use is subject to the Terms of Use and Notice. (20 of 20)9/10/2008 2:16:41 PM