DATA REVIEW
Efficacy
Data were presented from two 5-year-long studies of major short- to medium-term side effects of implant contraceptives not identified in clinical trials: the Postmarketing Surveillance of Norplant led by WHO and pre-introductory studies led by the Population Council. The evidence from those studies was that both Norplant and the two-rod levonorgestrel implant system are highly efficacious, with failure rates under 1 percent per year, thus providing reversible contraceptive protection essentially equal to that of permanent methods, that is, tubal ligation and vasectomy.
Safety
As with all hormonal methods, the contraceptive implant is unsuitable for some women and those contraindications are detailed in its labeling. The Post-marketing Surveillance and Population Council studies found serious adverse events to be extremely rare among implant users over 5 years of study and concluded that, in the settings where those studies were carried out, the method proved to be safe and well-tolerated.
The studies presented at the workshop on the biocompatibility of the polymer known as “silicone rubber” used in the implant produced the following information. First, while the capsules do provoke a typical local foreign-body reaction, the character of the biomaterial and its interface with tissue are not associated with pathological problems. Second, the silicone gel in breast implants is not the same, chemically or biologically, as the silicone rubber used in Norplant, and there are no data that indicate that the silicone elastomer used in Norplant acts as an adjuvant that could potentiate autoimmune disease.
A question that has been asked about the safety of the hormonal implant is whether its progesterone-like effect might, in human beings, produce the same thinning of vaginal epithelium and increased transmission of immunodeficiency virus effected in a monkey model. The report to the workshop was that at present, the quality of the available data does not permit any such conclusions but that until better human studies become available, clinical management of high-risk clients should emphasize protection from sexually transmitted infections through condom use and other safe sexual practices, with optimal contraceptive protection accorded secondary priority.
User Profiles
The characteristics of the women in international samples differed too substantially from country to country to permit easy generalizations. In the United States, the 1995 National Survey of Family Growth points to two groups
of Norplant users. The largest consists of predominantly young, single, minority women of lower socioeconomic status and educational levels, with one or more children, less likely to live in rural areas or in the northeastern portion of the country, and using the method primarily for spacing. A smaller group of older women of higher parity appears to be adopting the method as a long-term reversible alternative to tubal ligation.
Side Effects
Contraceptive implants produce side effects for many women, as described in the product labeling. By far the most common are changes in menstrual patterns, predominantly prolonged or irregular menstrual flow or increased bleeding. These tend to be frequent during the first 6 to 9 months of use, stabilizing by the end of the first year at a level that becomes acceptable to a majority of continuing users. The method also has nonmenstrual side effects which manifest with different frequency and relative importance in different populations and at different time points, but primarily include headache, vaginal discharge, weight gain, acne, pelvic pain, and mood alterations. The studies presented suggest that the simple presence of menstrual side effects does not reliably predict decisions to continue or discontinue implant use, but there are differences between continuers and discontinuers with respect to nonmenstrual side effects. Discontinuation rates associated with nonmenstrual side effects seem higher than those for menstrual side effects but no single side effect, menstrual or nonmenstrual, is consistently associated with decisions to discontinue use.
Continuation and Discontinuation
In studies to compare method use, implant continuation rates tend to be high relative to those of other reversible contraceptives. The overall pattern is that continuation rates are generally high through the first 2 years of use and not strikingly dissimilar from sample to sample, except in those studies that found discontinuation correlated with negative media coverage. Although there are great differences by country and although the data for the United States are scanty (partly because of low utilization), by the end of Norplant’s approved 5-year term of use, approximately one-half of those who originally chose it were continuing use, with a significant proportion of those who discontinued having done so to start a pregnancy. And while explicitly comparative data are also scant, continuation rates for the implant are high compared to those for other reversible methods.
Much remains to be understood before making broad assertions about reasons for continuing and discontinuing use of the contraceptive implant and about how those reasons differ from population to population over the reproductive cycle. Menstrual disturbances and other medical reasons are undeniably important yet, overall, reasons for retaining or removing Norplant are a complex blend of personal experience of side effects, “other-directed” variables like the wishes of
partners, and broader social influences, the passage of time, and changes in life plans. At least some women who stay with Norplant seem motivated to trade off side effects, even when burdensome in number or severity, for the convenience and efficacy they believe essential to greater control over their lives.
User Satisfaction
Information on user satisfaction is scarce. Data from clinic-based studies presented at the workshop found most women continuing Norplant use to be very satisfied with the method, while noting that they had not found it easy to get used to; their satisfaction level was slightly below satisfaction levels for Depo-Provera and the pill. The large majority of women continuing Norplant use would recommend it to others, a slightly smaller majority than for the other two methods but still high. Perceptions among those discontinuing use were much less positive: Very few of those discontinuing use indicated that they had been “very satisfied,” compared to sizable minorities of those who had discontinued use of Depo-Provera and the pill. Both women continuing use and those discontinuing saw the best features of Norplant as its convenience and effectiveness; fewer Depo-Provera and pill-users, whether they were continuing use or had discontinued, cited those attributes as those methods’ best features.
Postmarketing Surveillance
The report from the 5-year Postmarketing Surveillance of Norplant confirmed its value not only as a source of knowledge on adverse effects that cannot be identified in clinical trials, but as evidence that large-scale, longer-term surveillance studies using cohort methodology can now be considered feasible in developing countries.
Cost-Effectiveness
A “savings” model indicated that all forms of contraception, including dual-method use, are far less costly in the United States than an unintended pregnancy. In that array, the implant was shown to rank very high in terms of cost-effectiveness compared to other contraceptive methods, saving almost $14,000 over a 5-year period of use.
In sum, no good scientific reasons emerged in the workshop for not making Norplant available to all women for whom its use is not counterindicated in labeling.
TABLE 1 Lessons Learned
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The Delivery Side of the Health Care Equation Is a Commanding Factor The principal lesson concerning Norplant was that when used in a medically controlled environment, it proved to be a highly effective and safe contraceptive method, responsive to the needs of significant numbers of women. However, as the most technologically complex contraceptive method so far introduced onto the market and as one dependent for its provision on health care systems, Norplant’s utilization in large populations was never going to be simple, even though its introduction had been preceded by many years of basic and clinical research. Like all the most effective contraceptives now on the market, the method was designed to be applied in contexts requiring specific standards and, as the most technologically challenging of those methods, it demanded authentic competence in a minor surgical procedure in a clinic setting of good quality. These optimal contexts were not always secured: Extension of the method from limited populations to larger domestic and international settings was associated with shortcomings in application that confounded the value of the method with the quality of its delivery. The great preponderance of the method’s difficulties were those that have to do with larger, systemic difficulties in assuring provider training and evidence of competency, delivery system capacity for assuring the quality of all required services, the adequacy and appropriateness of counseling and communication, and the character and timing of consumer involvement. Providing and Receiving Training in New Contraceptive Methods Are Equally Critical Complicated implant removals were the basis, in 1994, of the first lawsuit involving Norplant and the subsequent flood of media coverage and litigation. This occurred despite the efforts by the method’s distributors and nonprofit intermediaries to train large numbers of providers in the technology. Those efforts were affected by a range of factors, each discussed in the course of the workshop and reflected in this report in the section on “Training for Insertion and Removal,” including, most importantly: • fast, high-volume program takeoff; • insufficient appreciation of the importance of proper insertions for easier removals; • limited practice in removal technique and predicting and preparing for complications; • lack of participation in training on the part of some providers who did insertions; • health care system structures that made uniformity of practice and assurance of competence difficult; and • insufficient sensitivity to the social, cultural, and personal dimensions of contraception, especially those particular to long-acting, “provider-dependent” contraceptives. The workshop material provided by presenters indicated that approximately 95 percent of removals were successful and without significant problems. While these were research sites and might be expected to have higher success rates, they indicate a potential that can be achieved and possibly improved. |
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Counseling and Communication Are Pivotal Case material indicated that intensive counseling was associated with better acceptance and continuation rates, partly because women deciding to use the contraceptive implant were carefully identified at the outset, partly because they were provided with enough information to choose freely, and partly because they acquired more complete understanding of what to expect in the form of side effects. There is anecdotal evidence that clinical response to management of side effects was less evenly successful and that women’s concerns about side effects were sometimes not given proper attention. The lesson here is a description of what communication about contraceptive choice would ideally be: a continuum spanning appropriate and intelligible product labeling; adequate provider training, collaboration between provider and client at the point of method choice; and support for clients in dealing with side effects and possible discontinuation, all the way to removal on demand or as approved efficacy ends and a new contraceptive choice must be made. This would optimally occur as truly two-way dialogue; information exchanged and necessary understandings would be complete and unconstrained by time; dialogue would be ongoing across the full course of contraceptive use; client participation in contraceptive choice would be truly voluntary; and the hierarchical distinctions between provider and client would be muted to the extent necessary for all this to happen. Taking Context into Careful Account Is Essential Experience with Norplant highlighted the fact that long-acting, provider-dependent contraceptive methods require special regard to ensure that decisions for their election and continued use are freely made and well informed. Failures in this respect not only have ethical implications but more broadly affect the proper utilization of the technology in question and its reputation. For example, although all such efforts failed, legislative and judicial attempts made in the United States to use Norplant coercively were perceived by some panelists and the constituencies they represented as evocative of some past attempts to restrict reproductive freedom that had disproportionately affected minority women. This had added to a residue of suspicion and affected objective assessment of the method. Lack of free choice, in method election and continuation, was also an issue in some developing countries, where it also led to negative public perceptions of the method overall, thus discouraging its use for many women for whom it would have been appropriate. Costs Matter The topic of cost-effectiveness raised questions for further consideration, importantly the meaning of costs, to both consumers and providers, for contraceptive availability and utilization. Real or imagined costs did act as barriers to Norplant use, notably in connection with removal for some women in some clinics. Workshop participants agreed that the entire subject of costs requires more creative thinking—about the cost of the method and its financing, about how to assure removal, and about clear policies of removal upon demand that are more effectively communicated to women considering the method. |
