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Hysteroscopic tubal sterilization: a systematic review of the Essure system

      Objective

      To update the evidence of the efficacy and safety of the Essure system. Female sterilization has undergone changes in the last decade. Besides laparoscopic tubal occlusion, the Essure system is now a viable option, with about 200,000 women sterilized using this method.

      Design

      The review is based on the report of the Alberta Heritage Foundation for Medical Research and completed with systematic literature searches up to April 8, 2008.

      Setting

      The Managed Uptake of Medical Methods program of the Finnish National Research and Development Center for Health and Welfare.

      Patient(s)

      Women over 30 years, who had been sterilized by the Essure method.

      Intervention(s)

      Hysteroscopic tubal sterilization using Essure system.

      Main Outcome Measure(s)

      Efficacy/effectiveness, adverse events, costs.

      Result(s)

      Sterilization by Essure can be performed under local anesthesia or with oral analgesics in ambulatory settings. However, sterilization is not immediate and women must use additional contraception for 3 months until permanent tubal occlusion is verified by transvaginal ultrasound, hysterosalpingosonography, hysterosalpingography, or pelvic radiography. The evidence on efficacy and safety is mainly available from short follow-up case series but shows good efficacy and safety of the Essure system. Only a few small risks are associated with the procedure. Two economic studies, one of which implemented Essure as an in-office procedure, suggest that Essure could be more cost-effective than laparoscopic sterilization, but more information on the total cost is needed.

      Conclusion(s)

      The Essure system appears to be safe, permanent, irreversible, and a less invasive method of contraception compared with laparoscopic sterilization.

      Key Words

      Female sterilization is a common method of contraception worldwide, with more than 100 million women having undergone sterilization by tubal occlusion or ligation (
      • Chapman L.
      • Magos A.
      Currently available devices for female sterilization.
      ). The most commonly used method has been a laparoscopic procedure in an operating room under anesthesia (with Falope Ring, Hulka Clips, Filshie Clips, coagulation, or cutting). Another method is a minilaparotomy incision (the Pomeroy method). Both procedures have their risks and adverse events: blind puncture, pain, bleeding, infection, postsurgical complications, and ectopic pregnancy (
      • Chapman L.
      • Magos A.
      Currently available devices for female sterilization.
      ). Hysteroscopic sterilizations have been described since 1850. Occlusions have been achieved with the aid of chemicals, various substances, and heat. The third-generation hysteroscopic methods include insertion of microinserts (Essure) and heat accompanied by a siloxane device (the Adiana system) (
      • Abbott J.
      Transcervical sterilization.
      ). The focus of the present systematic review is on hysteroscopic tubal sterilization using the Essure system, formerly known as the Selective Tubal Occlusion Procedure.
      The Essure system is manufactured by Conseptus (San Carlos, CA) and indicated only for permanent female birth control. It was launched in 2001 but the evidence about the effectiveness and safety is still based on short follow-up studies (1–2 years). The system comprises a fallopian implant and a delivery catheter. The implant is a spring-like device 40 mm in length and 0.8 mm in diameter. It consists of a stainless steel inner coil, nickel titanium (nitinol) elastic outer coil and polyethylene (PET) fibers. The device is placed into the fallopian tube using a standard hysteroscope (<5 mm) with a 5-French working channel with continuous physiologic saline flow. When released from the delivery system, the outer coil expands to 1.5–2.0 mm to anchor the microinsert to the fallopian tube. The optimal placement of the coils is with 3 to 8 coils remaining in the uterus to prevent migration toward the peritoneal cavity (Fig 1). The procedure can be done under local anesthesia with or without intravenous sedation as well as using oral analgesics alone (
      • Mino M.
      • Arjona J.E.
      • Cordon J.
      • Pelegrin B.
      • Povedano B.
      • Chacon E.
      Success rate and patient satisfaction with the Essure sterilisation in an outpatient setting: a prospective study of 857 women.
      ).
      Over a 3-month period the PET fibers elicit a benign tissue ingrowth, which blocks the fallopian tubes and results in permanent tubal occlusion (
      • Valle R.F.
      • Carignan C.S.
      • Wright T.C.
      STOP Prehysterectomy Investigation Group
      Tissue response to the STOP microcoil transcervical permanent contraceptive device: results from a prehysterectomy study.
      ). Women need to use additional birth control in the first 3 months following the procedure, after which fallopian tubal occlusion should be confirmed. Hysterosalpingography (HSG) has been the gold standard for such confirmation: a radiopaque contrast material is injected into the uterus to detect the closure of the fallopian tubes. Because of the potential adverse effect risks of HSG—infection, vasovagal reaction, uterine perforation and bleeding, relatively high cost, and pain (
      • Thiel J.A.
      • Suchet I.B.
      • Lortie K.
      Confirmation of Essure microinsert tubal coil placement with conventional and volume-contrast imaging three-dimensional ultrasound.
      )—alternative methods, such as pelvic radiography, have been suggested to verify the position of the microinserts (
      • Veersema S.
      • Vleugels M.P.
      • Timmermans A.
      • Brolmann H.A.
      Follow-up of successful bilateral placement of Essure microinserts with ultrasound.
      ). Transvaginal ultrasound assessment, however, is the least invasive method to locate the device and visualize the surrounding tissue (
      • Thiel J.A.
      • Suchet I.B.
      • Lortie K.
      Confirmation of Essure microinsert tubal coil placement with conventional and volume-contrast imaging three-dimensional ultrasound.
      ,
      • Kerin J.F.
      • Levy B.S.
      Ultrasound: an effective method for localization of the echogenic Essure sterilization microinsert: correlation with radiologic evaluations.
      ,
      • Weston G.
      • Bowditch J.
      Office ultrasound should be the first-line investigation for confirmation of correct Essure placement.
      ). The use of ultrasound with contrast material (hysterosalpingosonography [HSSG]) has been used for checking the patency of the tube only in pilot studies but can be used in cases where transvaginal ultrasound assessment is not sufficient (
      • Connor V.
      Contrast infusion sonography in the post-Essure setting.
      ).
      The Essure system has been approved in many countries and in the European Union since November 2001. Up to autumn 2007, some 200,000 women were using it. In the United States, the Food and Drug Administration issued premarket approval in July 2002 but required that the company provide 5-year follow-up data on its efficacy and safety.

      Methods

      This review was made by the Finnish Office for Health Technology Assessment, which is based in the National Research and Development Center for Welfare and Health (STAKES). The office was launched in December 2005 as part of the Managed Uptake of Medical Methods (MUMM) program, which is a joint venture involving all 21 hospital districts that provide specialized health care in Finland. The aim is to promote the use of evidence-based methods at all levels of health care in Finland by gathering, synthesizing, and disseminating information of health technology assessments.
      The present report is an update of the systematic review by the Alberta Heritage Foundation for Medical Research (AHFMR) on the efficacy and safety of the Essure system (
      AHFMR (Alberta Heritage Foundation for Medical Research)
      Hysteroscopic tubal sterilization system (Essure system).
      ) published in June 2006. The report included studies published in English up to 2005. We have complemented the AHFMR report with a systematic literature search defined for the MUMM program. Searches were made for the period 2004–2008, with the final search being made on April 8, 2008. The basic terms “Essure OR (Sterilization, tubal AND Hysteroscopy)” were completed during the years 2002–2007 with derivative terms. Systematic surveys from Medline, DARE, CLHTA, CLEED, and CDSR databases and studies about efficacy/effectiveness, safety, and feasibility in Medline, Cinahl, CCTR, and Journals-Ovid databases were searched by Ovid. A search was made of ongoing clinical trials at clinicaltrials.gov and controlled-trials.com/mrct.
      In addition, information from the Registry on Sterilizations was linked to three health care registers to find sterilization failures in Finland. Information on all deliveries after 22 gestational weeks and the possible use of in vitro fertilization was received from the Medical Birth Registry, information on all induced abortions was received from the Registry on Induced Abortions, and information on all spontaneous abortions and ectopic pregnancies was received from the Hospital Discharge Registry. All of these Finnish registers are mandatory, and they cover all sterilizations, births, induced abortions, and inpatient hospitalizations in both public and private hospitals. Permission to carry out the data linkages was given by the registry keeper (STAKES).

       Studies Found in Systematic Literature Search

      There are no randomized controlled studies of hysteroscopic sterilizations. The AHFMR report identified two multicenter case series, the phase II Study (
      • Kerin J.F.
      • Cooper J.M.
      • Price T.
      • Herendael B.J.
      • Cayuela-Font E.
      • Cher D.
      • et al.
      Hysteroscopic sterilization using a microinsert device: results of a multicentre phase II study.
      ) and the phase III pivotal study (
      • Cooper J.M.
      • Carignan C.S.
      • Cher D.
      • Kerin J.F.
      Selective Tubal Occlusion Procedure 2000 Investigators Group
      Microinsert nonincisional hysteroscopic sterilization.
      ), as well as four other studies, including one comparative study (
      • Duffy S.
      • Marsh F.
      • Rogerson L.
      • Hudson H.
      • Cooper K.
      • Jack S.
      • et al.
      Female sterilisation: a cohort controlled comparative study of Essure versus laparoscopic sterilisation.
      ) and three prospective case series (
      • Kerin J.F.
      • Munday D.N.
      • Ritossa M.G.
      • Pesce A.
      • Rosen D.
      Essure hysteroscopic sterilization: results based on utilizing a new coil catheter delivery system.
      ,
      • Ubeda A.
      • Labastida R.
      • Dexeus S.
      Essure: a new device for hysteroscopic tubal sterilization in an outpatient setting.
      ,
      • Litta P.
      • Cosmi E.
      • Sacco G.
      • Saccardi C.
      • Ciavattini A.
      • Ambrosini G.
      Hysteroscopic permanent tubal sterilization using a nitinol-dacron intratubal device without anaesthesia in the outpatient setting: procedure feasibility and effectiveness.
      ). Additionally, we found one prospective cohort study with 102 women (
      • Levie M.D.
      • Chudnoff S.G.
      Prospective analysis of office-based hysteroscopic sterilization.
      ). No postapproval reports on the 5-year follow-up were found for the phase II and pivotal studies.
      Conclusions on the effectiveness and safety of the Essure system are mainly based on the two multicenter case studies, which were sponsored by the manufacturer. Those studies included 745 women in total (phase II study: n = 227; phase III study: n = 518). Many of the subsequent studies are subgroup analyses of these two studies.

       Efficacy/Effectiveness

      In general, the studies suggest that the Essure method is safe, well tolerated, and effective in the short term. However, long-term data on safety, efficacy, effectiveness, and pregnancy rates are still unavailable. Some uncertainty comes from the relatively low follow-up rates. It should also be noted that most of the studies were funded by the manufacturer. Since its first introduction, the device has been improved, which has to be taken into consideration when comparing results from different time points.
      The bilateral placement success rate was 81%–98% (with up to two attempts). At 3 months after the procedure, 3.5% of the women could not rely on tubal occlusion, but after 6 months all women with successful placement showed total occlusion (
      • Kerin J.F.
      • Cooper J.M.
      • Price T.
      • Herendael B.J.
      • Cayuela-Font E.
      • Cher D.
      • et al.
      Hysteroscopic sterilization using a microinsert device: results of a multicentre phase II study.
      ). For quality assurance the tubal occlusion was verified by HSG, pelvic radiography, or transvaginal ultrasound assessment after 3 months. Transvaginal ultrasound is the least invasive and can be used alongside contrast infusion (
      • Connor V.
      Contrast infusion sonography in the post-Essure setting.
      ).
      The Essure system is safe, but still some unintended pregnancies have been reported. Sixty-four pregnancies out of an estimated 50,000 procedures were reported by the device manufacturer from 1997 through December 2005. Most of them occurred in patients without appropriate follow-up. Other causes included misinterpreted HSGs, undetected preprocedure pregnancies, and failure to follow product labeling guidelines (
      • Levy B.
      • Levie M.D.
      • Childers M.E.
      A summary of reported pregnancies after hysteroscopic sterilization.
      ).
      The sterilization is irreversible. If the woman regrets the operation, IVF or other embryo transfer procedures are possible, but the evidence is scant: Some case reports suggest that the Essure microinsert may be compatible with implantation and successful pregnancy outcomes after IVF (
      • Kerin J.F.
      • Cattanach S.
      Successful pregnancy outcome with the use of in vitro fertilization after Essure hysteroscopic sterilization.
      ,
      • Moses A.W.
      • Burgis J.T.
      • Bacon J.L.
      • Risinger J.
      Pregnancy after Essure placement: report of two cases.
      ).

       Adverse Events

      The data about adverse events are based on the phase II study and the pivotal study (total n = 745) (
      • Kerin J.F.
      • Cooper J.M.
      • Price T.
      • Herendael B.J.
      • Cayuela-Font E.
      • Cher D.
      • et al.
      Hysteroscopic sterilization using a microinsert device: results of a multicentre phase II study.
      ,
      • Cooper J.M.
      • Carignan C.S.
      • Cher D.
      • Kerin J.F.
      Selective Tubal Occlusion Procedure 2000 Investigators Group
      Microinsert nonincisional hysteroscopic sterilization.
      ). Tubal perforations were reported in 1%–3% of women, intraperitoneally placed implants in 0.5%–3%, and other unsatisfactory location in 0.5% of the cases. On the day of placement procedure, 1%–13% of the women reported pain, 30% stomach cramps, 11% nausea, and 7% bleeding or spotting. In three cases, the postoperative pain was so severe that the implants had to be removed (
      • Beckwith A.W.
      Persistent pain after hysteroscopic sterilization with microinserts.
      ,
      • Lannon B.M.
      • Lee S.Y.
      Techniques for removal of the Essure hysteroscopic tubal occlusion device.
      ).
      The stainless steel inner coil, and nitinol elastic outer coil of the implant may interfere with magnetic resonance imaging (MRI). However, 1.5-T MRI has been shown to be safe, and the 3-T field is under investigation (
      • Shellock F.G.
      New metallic implant used for permanent contraception in women: evaluation of MR safety.
      ). Computerized tomography and ultrasound produce no risks (
      • Shellock F.G.
      New metallic implant used for permanent contraception in women: evaluation of MR safety.
      ). The nitinol outer coil has not been shown to cause allergic reactions in the studies. The consensus from the training meetings suggests, however, that if there has been anaphylactic reaction to nickel previously, the implant should be avoided.
      As a foreign body, the Essure microinsert may cause tissue encapsulation. In cases where a second-look hysteroscopy was carried out within 12 months after the procedure, the complete tissue encapsulation of both microinserts had already occurred in 17% of the observations. Among cases evaluated from 13 to 43 months after the procedure, 25% showed evidence of complete encapsulation. The gradual tissue exclusion of the microinsert from the uterine cavity may make it more pregnancy-compatible after in vitro fertilization or other embryo transfer procedures (
      • Kerin J.F.
      • Munday D.
      • Ritossa M.
      • Rosen D.
      Tissue encapsulation of the proximal Essure microinsert from the uterine cavity following hysteroscopic sterilization.
      ).

       Costs

      Data on the cost-effectiveness of different sterilization methods are limited. The literature search identified two comparative studies on Essure and laparoscopic sterilization (
      • Hopkins M.R.
      • Creedon D.J.
      • Wagie A.E.
      • Williams A.R.
      • Famuyide A.O.
      Retrospective cost analysis comparing Essure hysteroscopic sterilization and laparoscopic bilateral tubal coagulation.
      ,
      • Levie M.D.
      • Chudnoff S.G.
      Office hysteroscopic sterilization compared with laparoscopic sterilization: a critical cost analysis.
      ). Those studies reported only the costs. The effectiveness (pain, pregnancies, or satisfaction) were not taken into account. Both of these studies came from the United States, where medical insurance may affect the total cost.
      The evaluation by Levie and Chudnoff (
      • Levie M.D.
      • Chudnoff S.G.
      Office hysteroscopic sterilization compared with laparoscopic sterilization: a critical cost analysis.
      ) calculated the actual cost difference in performing Essure sterilization in-office compared with laparoscopic tubal ligation performed in an operating room as an outpatient procedure in 2004. The calculation was based on the list of the various components required for each procedure. The costs of Essure included a preoperative visit (15 min) $41, procedure (40 min) $108, device $980, medicine $4, and postprocedure visit with HSG $233: total costs $1,374. Tubal ligation included preoperative visit (15 min) $41, laboratory $4, preparation $128, operating room time charges (90 min) $2,160, operating room salary $431, supplies $299, anesthesia $217, and postoperative visit $41: total costs $3,449. The cost difference was $2,075. Investment in equipment was not included. The effectiveness or complications were not followed, although a rough estimation of extra costs per case was made. In tubal ligation, $51 was added to the costs per case because of the 1.6% failure rate of tubal ligation, $71 because of the 0.9% risk of conversion from laparoscopy to laparatomy, and $176 because of other possible complications. In the Essure system, $272 was added to the costs per case because of a failure rate of 8% and subsequent tubal ligation. Sick leave days or other indirect costs were not taken into account.
      The study by Hopkins et al. (
      • Hopkins M.R.
      • Creedon D.J.
      • Wagie A.E.
      • Williams A.R.
      • Famuyide A.O.
      Retrospective cost analysis comparing Essure hysteroscopic sterilization and laparoscopic bilateral tubal coagulation.
      ) compared the institutional costs of Essure (n = 43) and laparoscopic bilateral tubal coagulation (n = 44) retrospectively in 2003, where both procedures were carried out in an operating room. The Essure system was applied with sedation or anesthesia. If the procedure failed, tubal coagulation was done at the same visit. Hysterosalpingography was done 3 months after the procedure. The tubal coagulation was carried out under anesthesia in an operating room. In the Essure system, further costs per case included $282 for physicians, $824 for equipment costs, $806 for operating room time charges and salaries of operating room staff, and $136 for medicine costs, for a total of $2,700. This included the costs of five tubal coagulations after Essure failures. The respective costs of tubal coagulation were counted as $371, $97, $1,871, and $136, for a total of $,2880. The cost difference was therefore $180. This study also excluded costs of investments, sick leave, complications, pregnancies, and indirect costs. Pain or other adverse events were not reported.
      Those two studies do not provide adequate evidence that Essure would be cost-effective in a Finnish health setting, which is different from that of the USA. However, they suggest that Essure, which can be performed in-office, could be more cost-effective than laparoscopic sterilization, but more information on total costs is needed. At least two ongoing studies are comparing the cost-effectiveness of Essure with laparoscopic sterilization, one in Canada and one in Finland.

       Essure in Finland

      Sterilization with Essure is an irreversible procedure and is used only as a method for contraception. In Finland, with 5.5 million inhabitants, the number of female sterilizations decreased by two-thirds between 1996 (∼12 000) and 2006 (∼4,000). The reason for this reduction has obviously been the widespread use of the levonorgestrel-releasing intrauterine system with possible health benefits in addition to contraception. The rate of male sterilizations have been stable, with <2,000 per year. In Finland, the Essure system was launched in 2002. Thus far, over 1,000 sterilizations have been made using this system. Between January 2002 and the end of December 2007, the Registry on Sterilizations included 848 Essure and 23,978 laparoscopic sterilizations. The linkage to other health registries showed no pregnancies with Essure but 103 (0.3%) with Filshie Clip.

      Conclusions

      Hysteroscopic tubal sterilization using the Essure system is safe, permanent, and irreversible. The counseling process should be thorough, including an explanation of benefits and risks and a discussion of alternative contraceptive methods, especially in cases with bleeding problems or dysmenorrhoea. Contraindications for use of Essure include uncertainty about the desire to end fertility, active pelvic infection, or difficult anatomic factors. The procedure can be made in an ambulatory setting under painkillers, which is probably the most cost-effective method. Potential risks of the procedure include pain, tubal perforation, and bleeding or spotting. Women are required to use alternative contraception for 3 months until the tubal occlusion has been demonstrated by transvaginal ultrasound, HSSG, HSG, or pelvic radiography. Because long-term follow-up data is weak, comparative trials are needed to assess long-term safety and cost-effectiveness.

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