New year, new implant: Time to add Nexplanon to contraceptive options

Training offered at 2012 Contraceptive Technology conferences

Get ready to offer women Nexplanon, the latest iteration of the contraceptive implant. The subdermal implant is similar to the Implanon device; however, the applicator has been redesigned to facilitate insertion of the implant in the appropriate subdermal position using one hand. As a protective mechanism, the applicator is rendered unusable if no implant is present in the applicator.1 The implant is radiopaque, which allows it to be located by two-dimensional X-ray, computed tomography, ultrasound scanning, or magnetic resonance imaging. Both devices are manufactured by Merck & Co. of Whitehouse Station, NJ.

As of November 2011, Nexplanon is available in the United States for healthcare providers who have completed the company's clinical training program on the administration of the device, says Sarah Pfeiffer, Merck company spokesperson. Merck has started training healthcare professionals on the insertion procedure for Nexplanon; clinicians can visit the product's web site, www.nexplanon-usa.com, to learn more about the training. (Nexplanon training will be offered at the upcoming Contraceptive Technology 2012 conferences.)

Those who already are trained in Implanon placement do not need to attend a full class, says Anita Nelson, MD, professor in the Obstetrics and Gynecology Department at the David Geffen School of Medicine at the University of California in Los Angeles. They can update themselves online at the product web site, she notes.

A small 2010 study of providers previously trained in Implanon insertion looked at satisfaction with the new Nexplanon inserter. Almost all investigators were satisfied with the new inserter from the first insertion onward, and all were satisfied or very satisfied after 12 insertions. The most frequently reported advantages included ease of use, one-handed action, and fast insertion time.1

Implanon still will be available as the transition to Nexplanon takes place, says Pfeiffer. The wholesaler acquisition prices for Implanon and Nexplanon are identical at $659.42, says Pfeiffer; however, the final transaction cost of Nexplanon varies based on the patient's insurance provider, she notes.

Implant safe, effective

The Nexplanon implant is approved by the Food and Drug Administration for up to three years of contraceptive use. It is extremely effective: to date, no pregnancies have been observed in prospective or retrospective cohort studies of Implanon, which included a total of more than 4,500 women and more than 7,000 women-years of exposure.2 In pregnancies reported to Merck, an analysis shows half had no implant present, and 38% were true product failures. One-fourth to one-third of the product failures occurred in women taking possibly intereacting drugs.2

The "get it and forget it" aspect of the contraceptive implant, as well as for intrauterine contraception, makes it an attractive choice for those who might have problems remembering to take a daily pill. More than 40% of young women ages 14-17 participating in the Contraceptive Choice Project in St. Louis chose the implant for contraception. Of women who chose the implant in the St. Louis project, 83% were still using the method at one year. The St. Louis project is designed to promote the use of long-acting reversible contraceptives and to assess satisfaction and discontinuation rates with various contraceptive methods.

A recent study was conducted to compare the incidence of repeat teen-age pregnancy over a 24-month period postpartum among users of Implanon, the combined oral contraceptive pill, the contraceptive injection depot medroxyprogesterone acetate (DPMA), barrier methods, or no method. Teens who chose Implanon were significantly less likely to become pregnant and were more likely to continue with the contraceptive method 24 months postpartum over other methods studied.3

Counsel on side effects

Like all progestin-only methods, Nexplanon causes bleeding changes in a large proportion of women.2 These changes might include amenorrhea, infrequent bleeding, irregular bleeding, or less often, prolonged or frequent bleeding. The best approach to reducing the impact of this side effect is to forewarn women about it and to counsel that it generally is not dangerous.4 From previous experience with the Norplant implant, research indicates that the quality of counseling before insertion can improve a patient's satisfaction with the implant and reduce the likelihood she will discontinue it due to side effects.5

The most common adverse reaction causing discontinuation of use of the implant in clinical trials was change in menstrual bleeding patterns, specifically irregular menses (11.1%). The most common adverse reactions reported in clinical trials were headache (24.9%), vaginitis (14.5%), weight increase (13.7%), acne (13.5%), breast pain (12.8%), abdominal pain (10.9%), and pharyngitis (10.5%).

Certain medicines might make Nexplanon less effective, according to the package insert. The insert advocates clinicians to check for use of the following drugs in women considering use of the method: barbiturates, bosentan, carbamazepine, felbamate, griseofulvin, oxcarbazepine, phenytoin, rifampin, St. John's wort, topiramate, and HIV medicines.

Both the World Health Organization (WHO) and the U.S. Medical Eligibility Criteria For Contraceptive Use (MEC) list only a few medical conditions that contraindicate use of implants (Category 3 or 4: Risks generally outweigh advantages, or use poses unacceptable health risks): unexplained, unevaluated abnormal vaginal bleeding; systemic lupus erythematosus with positive or unknown antiphospholipid antibodies; severe (decompensated) cirrhosis; benign or malignant liver tumor; current or past breast cancer; use of ritonavir-boosted protease inhibitors, certain anticonvulsants (phenytoin, carbamazepine, barbiturates, primidone, topiramate, oxcarbazepine), rifampicin, or rifabutin.2. The WHO guidance lists breastfeeding women less than six weeks postpartum and current deep venous thrombosis or pulmonary embolus as contraindications; the U.S. guidance sees breastfeeding women less than six weeks as 1 or 2 (no restrictions or advantages generally outweigh disadvantages), and current deep venous thrombosis or pulmonary embolus as a 2.

While Nexplanon is effective in preventing pregnancy, like other hormonal contraceptives, it offers no protection against sexually transmitted infections (STIs). As with other hormonal contraceptives, counsel on use of dual use with condoms for STI protection.

When to insert?

For women who are using no method, the implant may be inserted during days 1-5 of the menstrual cycle. For women who are on the combined hormonal pill, the implant can be inserted while they are taking active pills or within seven days after the last active pill. For those using the contraceptive injection, the implant may be inserted the day the next injection is due; for implants or intrauterine contraception, the implant may inserted the day of device removal.2

Remind women that Nexplanon is easily reversible. Research indicates that after Implanon removal, etonogestrel becomes undetectable in most users within a week, and most users ovulate within six weeks.2 The product package insert instructs women that if they do not want to get pregnant after the implant is removed, they should start another birth control method right away.

References

  1. Mansour D, Mommers E, Teede H, et al. Clinician satisfaction and insertion characteristics of a new applicator to insert radiopaque Implanon: an open-label, noncontrolled, multicenter trial. Contraception 2010; 82:243-249.
  2. Raymond EG. Contraceptive implants. In: Hatcher RA, Trussell J, Nelson AL, et al. Contraceptive Technology: 20th revised edition. New York: Ardent Media; 2011.
  3. Lewis LN, Doherty DA, Hickey M, et al. Implanon as a contraceptive choice for teenage mothers: a comparison of contraceptive choices, acceptability and repeat pregnancy. Contraception 2010; 81:421-426.
  4. Archer DF, Philput CB, Levine AS, et al. Effects of ethinyl estradiol and ibuprofen compared to placebo on endometrial bleeding, cervical mucus and the postcoital test in levonorgestrel subcutaneous implant users. Contraception 2008; 78:106-112.
  5. Chikamata DM, Miller S. Health services at the clinic level and implantable contraceptives for women. Contraception 2002; 65:97-106.