Initial Asian experience in hysteroscopic sterilisation using the Essure permanent birth control device

Authors


Dr A. Siow, Minimally Invasive Surgery Unit, KK Women's and Children's Hospital, 100 Bukit Timah Road, 229899 Singapore.

Abstract

Objective  To present our initial experience in the use of the Essure permanent birth control device in a predominately Asian population.

Design  A retrospective study.

Setting  Minimally Invasive Surgery Unit, KK Women's and Children's Hospital, Singapore.

Population  Eighty women seeking permanent birth control.

Methods  From 22 June 2001, women who sought sterilisation were counselled with regards to the various options of permanent birth control. Informed consent for hysteroscopic sterilisation was obtained only after the woman met the criteria for Essure permanent birth control. The sterilisation procedure was carried out without the need for general anaesthesia in a day surgery centre using the Essure permanent birth control device. The surgical details and post procedure follow up were analysed.

Main outcome measures  Feasibility and safety of the Essure permanent birth control device in Asians and its non-placement rate.

Results  No serious adverse events or complications were encountered in using the Essure device. No pregnancies have been reported in our series to date. A significant reduction in the Essure device non-placement rate (20.0%vs 4.0%, P= 0.021) and mean operation time (27.3 vs 19.6 minutes, P= 0.006) were seen when patients were pre-medicated with spasmolytic agent and analgesia.

Conclusions  The Essure permanent birth control device is safe and suitable for Asians. Its non-placement rate may be improved with pre-medication of spasmolytic agent and analgesia.

INTRODUCTION

Permanent birth control remains a popular choice among many couples in their reproductive years despite the advances in the various modes of contraception. In many Asian populations, women are active partners with regards to family planning. At our centre, with an annual birth rate of 15,000 to 17,000, we see tubal ligation being performed in excess of 1700 procedures per year. Although safe, this sterilisation procedure incurs the risk of general anaesthesia in addition to the surgical risk. The inherent risk of laparoscopy, which occurs primarily at the point of entry, is not different from other more advanced and complex laparoscopic procedures. The ideal sterilisation method is one that has maximal efficacy with minimal complications and adverse effects. Currently, the hysteroscopic approach appears to be the logical answer. It allows tubal access with minimal discomfort and risk. The superiority of hysteroscopic sterilisation is further enhanced by the avoidance of a skin incision and hence a much rapid post-operative recovery with lesser disruption to daily routines.

Over the years, many investigators have developed various tubal occlusive devices without much success. The inability to achieve a reasonable placement and occlusion rate was the major pitfall. The recent development of a new device called Essure has propelled hysteroscopic sterilisation as a superior and safe option of permanent birth control. The safety and efficacy of hysteroscopic sterilisation with the Essure device, formerly know as the Selective Tubal Occlusion Procedure (STOP) device, has been very favourable in its Phase II and the Pivotal trials.1,2 The study population in all reports regarding the Essure device to date have been non-Asians. We present our initial experience in the use of this device in a predominately Asian population.

The Essure device

The Essure device has received the CE mark by the European Union and endorsement by the Therapeutic Goods Administration in Australia. The Food and Drug Administration of USA have also recently approved it. In Singapore, the Ministry of Health and our hospital's ethics committee has approved its use locally since June 2001.

The Essure device is a dynamically expanding micro-insert consisting of a flexible inner coil made of stainless steel and a dynamic outer coil made of nickel titanium alloy (Nitinol). Running along and through the inner coil is a layer of polyethylene terephthalate (PET) fibres. These PET fibres serve to initiate a benign local tissue in-growth responsible for the occlusion of the fallopian tube.3

The Essure device is attached to a guide wire used for placement. During insertion, the outer coil is wound down to keep it in a low profile position. Upon release, the outer coil expands to anchor the Essure device firmly in the fallopian tube. The entire delivery system has been designed for one-handed release via an ergonomic handle, thumb-wheel and release button. Through the use of a release catheter that is sheathed by another hydrophilic delivery catheter, the Essure device can be deployed through a 5 French (1.7 mm internal diameter) operating channel of a 5.5-mm outer diameter hysteroscope.

Optimal placement of the Essure device at the proximal fallopian tube allows the device to span the uterotubal junction. This specific anatomy was chosen for insertion so that the device would be placed far enough into the tube to prevent expulsion from uterine contraction at menstruation, but would still be proximal enough to allow a portion of the device to trail into the uterus (demarcated by visualising four to eight coils of the Essure device at the ostia). This trailing portion at the ostia aids the assessment of optimal placement as well as the anchoring of the device (Fig. 1). With the Essure device in place, a local fibrous tissue in-growth induced by the PET fibres occurs in the surrounding tubal walls. Over a three-month period, the tissue in-growth totally occludes the tubal lumen effecting permanent birth control.4

Figure 1.

Essure device placement.

METHODS

We analysed our initial experience with the Essure permanent birth control over a period of 18 months from 22 June 2001 to 22 December 2002. All women who were not pregnant when seeking permanent birth control were given the options of conventional sterilisation or hysteroscopic sterilisation. Permanent birth control with the Essure device was only considered if the following conditions were satisfied:

  • 1The women were sure about their desire to end their fertility;
  • 2They have rejected other forms of birth control;
  • 3They were able and willing to use alternatively contraception for the first three months following Essure device placement;
  • 4They were available for follow up visits; and
  • 5They could understand and accept the non-placement rates, risk and benefits of the Essure device.

Women were advised against the Essure permanent birth control if they had any of the following:

  • 1Known tubal pathology preventing tubal cannulation,
  • 2Cervical or uterine neoplasia or its precursors,
  • 3Acute pelvic inflammatory disease,
  • 4Unexplained or abnormal uterine bleeding.

Women who had read and signed the informed consent form were then scheduled for Essure device placement the week after their normal menstruation. The procedure was performed in a day surgery centre setting. A urine pregnancy test was performed on the day of procedure to exclude pregnancy. Thirty minutes before the procedure, intramuscular Buscopan (Hyoscine-N-butylbromide) and Voltaren (Declofenac Sodium) were administered. These pre-medications were administered to all patients except in the first 30 cases.

The women were placed in a semi-lithotomy position for the procedure. The vulvar region was cleaned with chlorhexidine gluconate solution; the cervix was visualised using a Tolin's speculum and thoroughly cleaned with the same solution.

A rigid, continuous flow operating hysteroscope with an outer sheath diameter of 5.5 mm was used. Normal saline was used as the distension medium delivered via a constant pressure pump. The infusion pressure was kept at 50 mmHg to gently dilate the endocervical canal and simultaneously provide forward vision for the hysteroscopy. Mechanical dilatation of the cervix was not done unless the cervical os was two Hegar sizes smaller than the hysteroscope.

Paracervical block was not administered unless cervical dilatation was required. If needed, it was given through a dental syringe at the five and seven o'clock positions of the ectocervix. During the procedure, additional analgesia or sedation was administered as required via an intravenous catheter.

The entire hysteroscopic sterilisation procedure was displayed on video monitors in real time to allow the women to watch the operation. Digital documentation showing the Essure device position and the number of leading coils at each ostia was taken at the end of the procedure.

After the procedure, the women were prescribed an alternative contraception. A review appointment and hysterosalphingogram (HSG) was scheduled in three months time. The position of the Essure device and extent of Fallopian tube occlusion were then assessed. If it was deemed to be satisfactory, the patient was advised to rely solely on the Essure device for contraception. All women were also advised to return immediately should pregnancy occur.

RESULTS

A total of 80 women who met the inclusion and were not in the exclusion criteria gave consent for Essure device placement. The distribution of race in these women is shown in Table 1. The average age was 37.6 years (range 28–45 years) with 57 (71.3%) women above the age of 35 years. Their average gravidity was 2.9 (range 0–8) with 72 (90.0%) women having two or more children.

Table 1.  Distribution of race (n= 80).
RaceNo. of women (%)
Chinese71 (88.8)
Malay7 (8.8)
Indian1 (1.2)
Caucasian1 (1.2)

Essure device placement outcomes are presented in Table 2. Of the five women who had unilateral device placement in the first setting, only one had unsuccessful device placement of the contralateral tube eventually. This woman had a proximal occlusion of her right Fallopian tube detected later by HSG performed on two separate occasions, three months apart. It was likely that this proximal occlusion was the reason for the unsuccessful device placement in that tube.

Table 2.  Essure device placement outcome (n= 80).
OutcomeNo. of women (%)
Bilateral placement at first setting72 (90.0)
 
Unilateral placement at first setting5 (6.2)
Subsequent contralateral placement4
Eventual unsuccessful contralateral placement1a
 
Failure of bilateral placement at first setting3 (3.8)
Subsequent bilateral placement1
Eventual unsuccessful bilateral placement2b
 
Eventual successful bilateral placement77 (96.2)
Eventual unsuccessful bilateral placement(a + b)3 (3.8)

Two women eventually did not have successful bilateral placement of the Essure devices. The first patient finally underwent Filshie clip sterilisation after failing a second attempt at placing the device. At laparoscopy, hydrotubation demonstrated bilateral tubal patency with free spillage of dye. No structural abnormality was seen at laparoscopy and we arrived at the conclusion that tubal spasm was likely to be a factor during the unsuccessful placements. The second woman was not suitable for device placement because she had an extremely retroverted uterus with fallopian tubes significantly laterally placed. No further attempt was made to place the devices as the hysteroscopic procedure during the first attempt caused her much discomfort.

The mean operating time of all 85 attempts of Essure device placement was 22.8 minutes (range 6–85 minutes). There was one patient who was given a repeat dose of intramuscular Buscopan after an initial unilateral device placement. The second device was then placed at the same setting after a break, hence the total operating time of 85 minutes.

We identified two groups of women with respect to the administration of pre-operative smooth muscle relaxant (Buscopan) and analgesia (Voltaren). The number of women in each group and their operation times is shown in Table 3. Using χ2 test, the proportion of women with bilateral non-placement of the Essure device was significantly fewer when Buscopan and Voltaren were administered (20.0%vs 4.0%, P= 0.021). An analysis of the operation time using the Mann–Whitney U test also revealed a significantly shorter mean operation time when pre-medication was administered (27.3 vs 19.6 minutes, P= 0.006).

Table 3.  Pre-medication and operation time for Essure placement.
 First group: no pre-medicationSecond group: pre-medication given
  • *

    χ2 test: significantly fewer non-placement with pre-medication (P= 0.021).

  • #

    Mann–Whitney U test: significantly shorter mean operation time with pre-medication (P= 0.006).

Total no. of women3050
No. (%) of women with unsuccessful bilateral device placement on first attempt6 (20.0)2* (4.0)
Mean operation time (minutes) of successful bilateral device placement27.319.6#
Median operation time (minutes) of successful bilateral device placement21.515.0

Most of the women tolerated the procedure well. In the 85 attempts at Essure placement, 68 attempts (76.5%) did not require additional analgesia following pre-operative medication. Of the 17 that required additional analgesia, 15 were given paracervical blocks with 2% Lidocaine while one was sedated with intravenous Dormicum (Midazolam). The last woman requested that the procedure be performed under general anaesthesia, as it was a repeat attempt. She had wanted a laparoscopic sterilisation should placement of the device fail again.

There were no device-related or procedural-related adverse events during Essure placement in our experience. There were also no adverse reactions like vasovagal syncope or complications such as perforation of the fallopian tube or myometrium encountered.

Of the 77 women who had successful bilateral Essure placement, 63 (82%) had radiological evidence of bilateral occluded fallopian tubes with optimal Essure placement seen on HSG. In these 63 women who returned for HSG appointments, the bilateral tubal occlusion rate was 100%. Four women had radiological evidence of optimal Essure placement as seen on pelvic X-ray (Fig. 2) while the remaining 10 women defaulted their HSG appointments.

Figure 2.

Gull wing sign denoting optimal Essure device placement.

All women who returned for review had no complains with using the Essure device. There were no complains of menstrual disturbances or pelvic pain and all of the women did not complain of any symptoms relating to the presence of their devices.

As of 22 June 2003, 77 women had accumulated 1218 months of wearing the Essure device. All 67 women on regular follow up and with radiological evidence of tubal occlusion did not report any pregnancy. The remaining 10 women who have defaulted follow up were contacted through telephone and there were no pregnancies reported as well in this group.

DISCUSSION

The decision for permanent birth control should ideally be made after an in-depth discussion with couples seeking contraception. It is reasonable to assume that the choice of sterilisation be the one that carries the least surgical risk with the most effective contraception. Vasectomy undoubtedly falls within these criteria.

In our Asian population, vasectomy is not well accepted and very unpopular among the male population. As a result, the responsibility of permanent birth control usually becomes that of the woman. Postpartum sterilisation and interval laparoscopic ligation with Filshie clips are the two most common forms of permanent birth control in our population. Although the surgical risks with these procedures are low, complications can and do happen. In addition, the failure rates of these sterilisation procedures compare poorly with vasectomy.5

A safer and more effective mode of permanent birth control would enable our women to have the option of avoiding these unfavourable surgical risks and failure rates. Hysteroscopic sterilisation is potentially an ideal method of achieving permanent birth control. It negates the risk of an abdominal operation as well as the risk of general anaesthesia.

Friorep6 initiated the first attempt at hysteroscopic sterilisation by passing a nitric acid coated probe through the cervix to the tubal ostia to cause chemical stricture. Subsequent efforts to achieve hysteroscopic sterilisation were largely unsuccessful due to the lack of an agent or device that could securely occlude the fallopian tube. Sclerosing agents like quinacrine7 infused into the tubal ostia had high failure rates while various tubal ostia plugs8,9 could not stay in place reliably. Kerin et al.10 felt that for effective hysteroscopic sterilisation, occlusion of the uterotubal junction is vital. The failure of tubal blocking devices of the past was thus thought to be their inability to site across this key anatomical position.

With the development of the Essure device, this problem can now be overcome. The dynamic expanding outer coil mechanism of the device ensures proper anchorage that was difficult to achieve in previous designs. This dynamic mechanism also achieves the ‘one size fits all’ objective. With the aid of the ergonomic delivery system and the state-of-the-art video-hysteroscopy of today, placing the device optimally across the uterotubal junction is now possible. To achieve occlusion, the ‘solid state’ sclerosing agent PET fibres have been shown to be effective.2 An additional advantage of the PET fibres compared with the liquid sclerosing agents is the elimination of the risk of intraperitoneal spillage leading to potential chemical peritonitis.

In the first clinical study on the Essure permanent birth control, Kerin reported that it is a safe and well-tolerated procedure, with high patient acceptance. In addition, it has the advantages of rapid recovery, minimal side effects and lack of awareness of the presence of the device. Most importantly, the results so far point to the fact that the Essure permanent birth control is an effective contraception.8

Our initial experience concurred with Kerin's findings that the Essure device is a safe form of permanent birth control, as we did not encounter any complications or adverse reactions during device placement. The women in our series also shared similar favourable experiences in terms of the lack of side effects and awareness of the presence of their devices. There has also been no pregnancy encountered in our series to date.

In all the trials on the Essure permanent birth control conducted to date, the study population were primarily Caucasian women. As our centre was the first to provide this form of contraception in a largely Asian population (98.8% in our series), we wanted to determine whether the clinical data from the earlier series of Caucasian women are applicable to our smaller-framed Asian women. Our results suggest that despite the possibility of anatomical differences between the races, the Essure device is equally suitable for the non-Caucasian women in terms of safety, placement rates, tubal occlusion rates and patient acceptance.

During the study period, 1411 women requested postpartum or post-abortion sterilisation and 349 women requested interval tubal ligation. As the Essure device was offered to women who were not pregnant when seeking permanent birth control, only the latter group of women was approached. This resulted in a take up rate of 22.9% (80/349) for this new sterilisation technique at our centre. Despite the favourable results of the Phase II and Pivotal trials, this is a new technique of contraception, involving insertion of a permanent device. As we wanted to keep procedural complications to a minimum, only one hysteroscopist fully trained in Essure device placement provided the service. This factor, coupled with the strict inclusion and exclusion criteria of the study, limited the number of patients recruited for Essure device placement.

Perhaps the main setback of the Essure permanent birth control is the reported non-placement rate of 15%.8 Looking at only the initial attempts in our series, the non-placement rate for bilateral placement was 10.0% (8/80). However, after repeated attempts, only three women had unsuccessful bilateral placement eventually. Our final non-placement rate for bilateral fallopian tubes was thus 3.8% (3/80).

Most of the cases of non-placement occurred in the beginning of our series. Tubal spasm was suspected as the main reason for failure in six women. In one of them, laparoscopic hydrotubation actually confirmed patent tubes. The fact that tubal spasm may be a hindrance to hysteroscopic sterilisation is not surprising. Tubal spasm has commonly been encountered in hysterosalpingography and hydrotubation at laparoscopy, giving rise to false positive result of tubal blockage. To overcome this problem, Buscopan, a quaternary ammonium derivative that exerts a spasmolytic action on smooth muscle was pre-medicated to the second group of women. Voltaren was also added for its analgesic effect. An analysis of our results revealed that this pre-medication significantly improved the device placement rates. With Buscopan preventing or relieving tubal spasm, there may be less resistance to threading the Essure device into the uterotubal junction of the fallopian tube. This could possibly explain the significantly shorter operation time in the second cohort as well.

Although we cannot eliminate the confounding factors associated with the initial learning curve of the procedure, we feel that its effect is small. This is because all the cases were carried out in the presence of one skilled hysteroscopist specially trained in Essure permanent birth control. In addition, the same group of dedicated and experienced nursing staff, specifically trained in operative hysteroscopy, provided surgical assistance. Hence, we believed that pre-medicating with Buscopan and Voltaren may have contributed to the lower non-placement rate of the Essure device.

CONCLUSION

Hysteroscopic sterilisation shows promise as a convenient, less invasive and low risk approach to achieving permanent birth control. In women with elevated risk for laparoscopy, such as the presence of previous midline laparotomy or morbid obesity, hysteroscopic sterilisation would be ideal.

Hysteroscopic sterilisation using the Essure permanent birth control has been shown to be a well tolerated, safe and effective form of contraception. Our study showed that it is also suitable for the smaller-framed Asian women.

The final challenge for the Essure device to be considered as the ideal permanent contraception may well be the reduction of non-placement rate. It is our experience that the use of a pre-operative spasmolytic agent like Buscopan and an analgesic like Voltaren has a positive impact in reducing tubal spasm leading to a lower non-placement rate. It would be prudent for a larger randomised controlled trial to further substantiate this finding.

Acknowledgments

The authors would like to thank Dr Kelvin Tan, Mr Chung Hing Ip and SSN Chia Yit Ching for their invaluable comments and assistance.

Accepted 8 June 2004

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