Everything you need to know about the contraceptive implant
FDA approval means US women now have a progestin-only implant among their birth control options
IN THIS ARTICLE
Subdermal placement is imperative for efficacy and easy removal.
Insertion technique
Have the patient lie on the examination table with her nondominant arm flexed at the elbow and her hand next to her ear. Identify and mark the insertion site using a sterile marker, and apply any necessary local anesthetic. The insertion site should be 6 to 8 cm above the elbow crease on the inner aspect of the arm. Also mark the skin 6 to 8 cm proximal to the first mark; this serves as a guide during insertion.
Remove Implanon from its package and, with the shield still on the needle, confirm the presence of the implant (a white cylinder) within the needle tip. Remove the needle shield, holding the inserter upright to prevent the implant from falling out. Apply countertraction to the skin at the insertion point and, holding the inserter at an angle no greater than 20 degrees, insert the needle tip into the skin with the beveled side up. Lower the inserter to a horizontal position, lifting the skin with the needle tip without removing the tip from the subdermal connective tissue, and insert the needle to its full length.
Next, break the seal of the applicator by pressing the obturator support, and rotate the obturator 90% (in regard to the needle) in either direction. At this point, the insertion process is the opposite of an injection: Hold the obturator in place and retract the cannula.
After insertion, the implant may not be visible but must remain palpable.1
Timing the insertion. Placement should occur at one of the following times:
- For women who have not been using contraception or who have been using a nonhormonal method, insert the implant between days 1 and 5 of menses.
- For women changing from a combination or progestin-only OC, insert the implant any time during pill-taking.
- For women changing from injectable contraception, insert the implant on the date the next injection is scheduled.
- For women using the IUD, insertion can take place at any time.
Additional birth control for 7 days
Advise all women to use an additional barrier method of contraception for 7 days following insertion, unless insertion directly follows an abortion (in which case, no additional contraception is needed).
In all cases, exclude pregnancy before inserting the implant, although there is no evidence that hormonal contraceptives cause birth defects.
Removal technique
The ENG implant can be removed at any time at the woman’s discretion, but will remain effective for 3 years.
Removal requires a 2-mm incision at the distal tip of the implant. The other end of the rod is then pushed until the rod pops out of the incision.9
Mean removal time is 2.6 to 5.4 minutes.22
In rare cases, the ENG implant cannot be found when the time comes for removal, and special procedures, including sonographic determination of location and sonographically guided removal, are required.
Pain, swelling, redness, and hematoma have been reported during insertion and removal.
Because ovulation resumes rapidly following removal, women still desiring contraception should begin another method immediately or have a new rod inserted through the removal incision.
Tell patients to expect altered bleeding
Side effects associated with the ENG implant include menstrual irregularities:
- infrequent bleeding, 26.9%
- amenorrhea, 18.6%
- prolonged bleeding, 15.1%
- frequent bleeding, 7.4%
Other effects include weight gain, 20.7%; acne, 15.3%; breast pain, 9.1%; and headache, 8.5%.8,18
These symptoms rarely provoke discontinuation. Women using any progestin-only method will have changed bleeding patterns; it is estrogen, along with regular progestin withdrawal, that provides predictable uterine bleeding.23,24
A comparison of bleeding patterns in ENG implant users and LNG implant users found a lower mean number of bleeding/spotting days with the former (15.9–19.3 vs 19.4–21.6; P=.0169).25 Because total uterine blood loss is reduced, users of progestin-only contraceptives (as well as OCs) are less likely to be anemic.
The same comparison25 found that users of ENG implants had more variable bleeding patterns than users of LNG implants. Unfortunately, it is impossible to predict which patterns a woman is likely to experience.
The ENG implant reduced or eliminated menstrual pain in 88% of women who previously experienced dysmenorrhea; pain increased in only 2% of ENG implant users.18
Most women liked the implant
Despite side effects and the need for a physician to insert and remove the implants, most women are satisfied with the method, citing its long duration, convenience, and high efficacy.26,27
Discontinuation rates
Nevertheless, some women do choose to discontinue the method before 3 years are up. Discontinuation rates range from 30.2% in Europe and Canada to 0.9% in Southeast Asia.18,22 Bleeding irregularities are the most commonly cited reason for discontinuation, as they were for Norplant.
