(Published July 2008)
The vast majority of reproductive-age women are candidates for the single-rod implant. Even women who have been satisfied with their current contraception should be given sufficient information about the variety of methods now available to make an informed choice based on their individual life circumstances. Written information should be provided as part of counseling materials and health professionals should be sensitive to the woman’s literacy level and language requirements.
Providers should discuss the following topics with women who are candidates for the single-rod implant in addition to general information about all contraceptive methods:
- Description of the Implant — Show the woman the implant and applicator. Talk about being able to palpate the rod but not see it after insertion.
- Efficacy — Explain that effective contraceptive methods result in fewer pregnancies. Use the graphic found in Figure 6, or patient education materials at www.arhp.org/contraception to describe the efficacy of the single-rod implant in relation to other methods of contraception. Explain that Implanon™ provides three years of continuous pregnancy prevention but does not prevent against sexually transmitted infections (STIs)/diseases or human immunodeficiency virus (HIV).
- Return to Fertility — Remind the women serum levels of etonogestrel drop quickly after removal and fertility will return rapidly. An alternate contraceptive is needed if pregnancy is not desired when discontinuing Implanon.
- Managing Potential Side Effects — Remind women to report any adverse effects to the health care provider. Remind women to tell all of their health care providers, especially prescribers, of their implant use to help avoid drug interactions. Encourage women to discuss the use of any herbal or over-the-counter products that may also alter the effectiveness of their contraceptive method.
- Insertion and Removal — Refer to www.implanon-usa.com/HCP/insertionRemoval/ for guidance to walk the woman through the procedure.
- Follow-up — Remind patients to plan on a future removal no later than three years from insertion. After insertion the patient should be able to feel the implant.
- Bleeding Patterns — Satisfaction with the method is highly dependent on acceptance of the method’s limitations, especially with respect to bleeding irregularities. Women should be counseled that amenorrhea does not signal pregnancy.
- Abdominal Pain — Have women report any instances of abdominal pain, which might be a sign of ectopic pregnancy or ovarian cysts.
Continuation rates for all methods of contraception are often quite low. Up to 62 percent of women using oral contraceptives discontinue use at 1 year.2 This rate can be further improved upon with adequate counseling. Implanon has an advantage, as continuation rates are generally higher for methods requiring removal by a health care professional. A post-marketing observational study of 324 British women using the singlerod implant found that 75 percent continued at 1 year; 59 percent continued at 2 years; and 47 percent continued at 2 years nine months.2
Bleeding irregularities are cited as the most common reason for discontinuing the single-rod implant in clinical trials and in post-marketing studies. Discontinuation due to bleeding changes was reported by only 11.1 percent of women in the clinical trials. Up to 40 percent of women discontinued due to bleeding irregularities in real-life situations. This greater percentage reflects the realities of an uncontrolled clinical setting and reinforces the need for adequate patient counseling. Other reasons for discontinuation of the single-rod implant are shown in Figure 7. Keep in mind that implants have the lowest discontinuation rates of all reversible contraceptive methods; oral contraceptives and the intrauterine device (IUD) have the next lowest set of discontinuation rates.
The contraindications listed in the physician insert for the single-rod implant are similar to those listed for progestin-only contraceptives. Clinicians must use their judgment regarding the clinical relevance of these contraindications, weighing the benefit/risk ratio for each woman. There is insufficient evidence relative to the safety of the single-rod implant in women with a history of thromboembolic disease. Some progestin-only contraceptives may increase the risk of thrombosis, although this increase is substantially less than with combined oral contraceptives.
The World Health Organization recommends not using any progestin-only contraceptive in women with current deep vein thrombosis/pulmonary embolism (DVT/PE) because of the potential risk of venous thrombosis unless other more appropriate methods are not available or not acceptable to the woman.
All other women (those with a history of DVT/PE, a family history of DVT/PE, and major and minor surgery candidates) can generally use subdermal contraceptive implants and other progestin-only methods.4
- World HealthOrganization. Comparing typical effectiveness of contraceptive methods. Geneva: World Health Organization, 2006. Available at: www.fhi.org/nr/shared/enFHI/Resources/EffectivenessChart.pdf. Accessed October 31, 2007.
- Lakha F, Glasier AF. Continuation rates of Implanon in the UK: data from an observational study in a clinical setting. Contraception. 2006 Oct;74(4):287-9.
- Agrawal A, Robinson C. An assessment of the first 3 years’ use of Implanon in Luton. J Fam Plann Reprod Health Care. 2005 Oct;31(4):310-2.
- WHO. World Health Organization. Medical Eligibility Criteria for Contraceptive Use. 3rd ed. 2004. www.who.int/reproductive-health/publications/mec/5_pocs.pdf. Accessed August 24, 2007.
About Audrey Kelly, PharmD