Nexplanon, the etonogestrel contraceptive implant, is now FDA-approved for five years of continuous use. The approval, based on clinical trial data showing zero pregnancies and no new safety concerns during years four and five, extended the previous three-year label. The side-effect profile over the longer duration looks similar to what users experience in the first three years, though the details of bleeding changes, weight, and other effects are worth understanding before you commit to half a decade with a matchstick-sized rod in your arm.
What the FDA Approval Actually Means
For years, the implant carried a three-year label in the United States, even as accumulating evidence suggested it worked longer. Clinicians who kept up with the research sometimes recommended “extended use” beyond three years, but that was off-label, meaning it lacked formal regulatory backing.1PubMed Central. Offering extended use of the contraceptive implant via an implementation science framework: a qualitative study of clinicians’ perceived barriers and facilitators The FDA’s updated approval changed that. The supporting clinical trial reported a Pearl Index of 0.0 pregnancies per 100 woman-years during years four and five, with no new safety signals identified during extended use.2Contemporary OB/GYN. FDA approves 5-year use for etonogestrel implant 68 mg contraceptive
This isn’t just a paperwork update. The practical difference is that you no longer need a provider willing to go off-label, and insurance coverage is more straightforward when you keep the implant for its full approved duration. It also means the cost per year drops considerably when spread over five years rather than three.
Why the Implant Still Works at Year Five
The implant releases etonogestrel, a synthetic progestin, into your bloodstream at a slow, steady rate. This hormone does two main things: it suppresses ovulation by dialing down the hormonal signals that trigger egg release, and it thickens cervical mucus so sperm have a much harder time reaching an egg.3Contraception. Progestin implants for women: update on mechanism of action The concern with a longer lifespan has always been whether hormone levels drop too low to keep doing those jobs reliably.
Blood measurements tell a reassuring story. At the end of the third year, the median etonogestrel level in implant users was around 208 pg/mL. By the end of year four it was about 166 pg/mL, and by the end of year five it was roughly 153 pg/mL. The threshold needed to prevent ovulation is approximately 90 pg/mL, and median levels stayed well above that mark across all body-weight categories through the fifth year.4PubMed Central. Prolonged use of the etonogestrel implant and levonorgestrel intrauterine device: 2 years beyond Food and Drug Administration-approved duration A separate study tracking implant users for up to five years recorded no pregnancies among thousands of months of observation, with a cumulative pregnancy rate that was statistically equivalent to other long-acting implant types.5PubMed Central. Extended use up to 5 years of the etonogestrel-releasing subdermal contraceptive implant: comparison to levonorgestrel-releasing subdermal implant
Bleeding Changes Are the Biggest Complaint
If there is one side effect that dominates the conversation around Nexplanon, it is unpredictable bleeding. Irregular menstrual patterns are the most commonly reported issue.6PubMed Central. A systematic review on clinical effectiveness, side-effect profile and meta-analysis on continuation rate of etonogestrel contraceptive implant That umbrella term covers a wide range of experiences. In one large review, roughly a fifth of users stopped having periods altogether, about a third had infrequent bleeding, and around 18% experienced prolonged bleeding episodes. A smaller group, about 7%, had more frequent bleeding than normal.7PubMed. The effects of Implanon on menstrual bleeding patterns
What makes this frustrating for many people is the unpredictability. Even among users whose total number of bleeding days was fewer than a typical menstrual cycle, those days showed up at irregular intervals. You might go weeks with nothing and then spot for ten days. For some, the pattern settles into something tolerable after the first several months. For others, it stays erratic. No reliable way exists to predict beforehand which camp you will fall into, which is partly why bleeding disturbances are one of the leading reasons people have the implant removed early.
Does Nexplanon Cause Weight Gain?
Weight gain is one of the most commonly cited fears about hormonal contraceptives, and Nexplanon is no exception. The picture here is more nuanced than social media conversations might suggest. In a controlled study comparing implant users to a control group, there was no statistically significant difference in weight change at one or three months. Women in both groups gained minimal weight, and implant users were not at higher risk of gaining more than about two kilograms compared to the control arm.8PubMed Central. Association of Progestin Contraceptive Implant and Weight Gain
Over longer periods, the data gets messier. A study of 350 ethnically diverse implant users found a mean weight change of about 3.8 kg over the course of use. But the range was enormous, spanning from losing more than 27 kg to gaining more than 26 kg. Interestingly, self-reported perception of weight gain agreed poorly with measured weight change, meaning many people who felt they had gained weight had not gained much, and vice versa.9PubMed Central. An Exploratory Analysis on the Influence of Genetic Variants on Weight Gain among Etonogestrel Contraceptive Implant Users Genetics may play a role: certain variants of the estrogen receptor gene were associated with substantially more weight gain. Women who were homozygous for one particular variant gained on average about 10 kg more than other participants.10Fertility and Sterility. Genetic variants associated with weight gain during etonogestrel contraceptive implant use Higher baseline BMI was also consistently linked to more weight change during implant use, regardless of genetic profile.
The takeaway is that Nexplanon does not cause weight gain for most users in any clinically meaningful way, but a subset of people may gain weight, potentially influenced by their genetic makeup. If you notice significant changes, it is worth discussing with your provider rather than assuming it is an inevitable consequence of the implant.
Does Body Weight Affect How Well the Implant Works?
This is a separate question from whether the implant causes weight gain, and the answer is encouraging. Among nearly 1,400 woman-years of implant use, only one pregnancy occurred, and it was in a participant with a BMI in the obese range. The overall failure rate stayed below 1 per 100 woman-years regardless of BMI category, and there was no statistically significant difference in failure rates between normal weight, overweight, and obese users.11PubMed Central. Contraceptive Failure Rates of Etonogestrel Subdermal Implants in Overweight and Obese Women A systematic review looking specifically at this question confirmed that the implant’s effectiveness in women with overweight and obesity falls within the same range as published data for all users, with no evidence of reduced effectiveness at higher BMI.12BMJ Sexual & Reproductive Health. Effectiveness of the etonogestrel subdermal implant in users with overweight and obesity: a systematic literature review
This sets the implant apart from some other hormonal methods where body weight may affect drug absorption or metabolism. The blood-level data mentioned earlier showed that median etonogestrel concentrations stayed above the ovulation-suppression threshold for all BMI classes through the fifth year of use.4PubMed Central. Prolonged use of the etonogestrel implant and levonorgestrel intrauterine device: 2 years beyond Food and Drug Administration-approved duration
Medications That Can Undermine the Implant
One genuinely important safety concern is drug interactions. Etonogestrel is broken down in the liver by an enzyme called CYP3A4, and certain medications ramp up that enzyme’s activity, which can clear the hormone from your system faster than the implant can release it. An analysis of adverse event reports found a strong association between CYP3A4-inducing drugs and contraceptive failure in implant users.13PubMed Central. Comparison of contraceptive failures associated with CYP3A4-inducing drug-drug interactions by route of hormonal contraceptive in an adverse event reporting system
The medications most likely to cause trouble include certain anti-seizure drugs, the tuberculosis antibiotic rifampin, and some antiretroviral medications used for HIV. The herbal supplement St. John’s wort is another well-known CYP3A4 inducer. If you take any of these, the implant may become less reliable, and your provider should discuss backup or alternative contraception. This interaction applies whether you are in year one or year five, though it becomes more relevant in later years when hormone levels are already lower.
Bone Density Over Time
Because etonogestrel partially suppresses estrogen activity, there has been some concern about its effect on bone health with prolonged use. A three-year longitudinal study found that implant users had a roughly 6% decrease in bone mineral density at the distal radius compared to their baseline measurements.14PubMed Central. A three-year longitudinal evaluation of the forearm bone density of users of etonogestrel- and levonorgestrel-releasing contraceptive implants A separate study comparing long-term implant users to controls confirmed lower bone density at the distal radius and ulna among implant users, though actual osteoporosis was rare in both groups.15PubMed. Bone mineral density in women using the subdermal contraceptive implant Implanon for at least 2 years
The clinical significance of these findings is debated. The losses were measured at specific forearm sites and were modest. Bone density at other sites, like the ultra-distal radius, showed no significant change. This is quite different from the bone-density warnings associated with the injectable progestin (Depo-Provera), where losses tend to be larger and more concerning. Still, if you have existing risk factors for osteoporosis, this is a conversation worth having with your provider before committing to five full years of use.
The Insertion and Removal Experience
Nexplanon is placed just under the skin of your inner upper arm through a small incision, and the procedure takes a couple of minutes. One large observational study tracked over 5,000 removal procedures and found that all but one were successful. That single failure involved an implant lodged in deep muscle tissue, which is uncommon. The incidence of insertion problems, including cases where the device was placed too deeply or partially inserted, was about 13 per 1,000 insertions.16PubMed. Real world data on Nexplanon® procedure-related events: final results from the Nexplanon Observational Risk Assessment study (NORA)
From a practical standpoint, extending use to five years means one fewer removal-and-reinsertion cycle compared to the old three-year label. If you planned to use the implant for six years, that used to mean two devices and two sets of procedures. Now it means one device for five years and just one replacement. That is less time in the office and less tissue handling at the insertion site.
Why Many People Remove It Early
Despite its excellent efficacy, continuation rates for the implant can be surprisingly low. One study found a one-year continuation rate of 62% and a three-year rate of just 8%.17PubMed Central. Continuation Rates of the Etonogestrel Implant and Factors Associated With Early Discontinuation In a study focused on adolescents, about 79% kept the implant through the first year, 59% through year two, and only 26% through year three. The most common reason for removal in that age group was device expiration rather than dissatisfaction.18Journal of Pediatric and Adolescent Gynecology. Subdermal Contraceptive Implant Insertion Trends and Retention in Adolescents
The gap between how effective the implant is and how many people actually keep it in tells you something. Bleeding irregularities, perceived weight gain, mood changes, and other quality-of-life issues drive early removal even when the device is working perfectly as contraception. Whether the five-year label will improve continuation rates remains to be seen. It could help in cases where people were removing the implant simply because it had “expired,” but it won’t change the side-effect experience that pushes many users to switch methods.
How Five Years Affects the Cost Picture
Long-acting methods like the implant have high upfront costs but become cheaper per year the longer you keep them. A cost analysis comparing the five-year implant to other contraceptive options found that the implant was associated with the fewest unintended pregnancies and the lowest total per-woman cost over five years. The estimated five-year cost per woman was roughly $3,400 for the implant, compared to about $5,300 for a three-year IUD and around $4,700 for a five-year-or-longer IUD.19PubMed. A five-year cost-consequence analysis of extended-use etonogestrel implant versus other contraceptives Cost offsets began in the first year and grew through year five, largely because the implant’s near-perfect efficacy translates to fewer pregnancies and associated healthcare costs.
Of course, these numbers depend heavily on insurance coverage, which varies. Under the Affordable Care Act, most insurance plans cover FDA-approved contraceptives without cost-sharing, meaning the upfront expense may be zero for you. But if you are paying out of pocket or navigating coverage gaps, the math favors keeping the implant for its full duration rather than replacing it early.
The Drug Interaction Risk in Later Years
The CYP3A4 interaction issue deserves a second look specifically in the context of extended use. Etonogestrel levels naturally decline each year. A level of 153 pg/mL at year five still clears the 90 pg/mL ovulation threshold with some room to spare, but the margin is tighter than it was at year one or two. If a medication that accelerates etonogestrel metabolism enters the picture during year four or five, the already-lower baseline means you could theoretically be pushed closer to or below that threshold faster than someone in their first year of use.
No study has specifically quantified this interaction at years four and five versus earlier time points, so the recommendation remains the same regardless of how long the implant has been in place: tell every prescribing clinician you have an implant, and if you need to start a CYP3A4-inducing medication, work with your provider on a plan. But the logic of tighter margins later in the implant’s life is something to keep in mind, especially if you are managing a chronic condition that requires these medications.
How Quickly Fertility Returns After Removal
One of the advantages of the implant over some other long-acting methods is that fertility returns rapidly after removal. Etonogestrel clears from the bloodstream within days, and ovulation typically resumes within a few weeks. This is true whether you remove the implant at year three or year five, because the mechanism is the same: once the hormone source is gone, the body’s own hormonal signaling picks back up quickly. For people who want long-term but reversible contraception through their twenties or early thirties, the five-year duration makes the implant an even more attractive bridge between “not now” and “eventually.”
Clinicians sometimes worry about counseling on extended use because the evidence base, while strong, was until recently built on off-label data rather than a formal FDA-approved indication. A qualitative study found that providers identified uncertainty about the evidence and concerns about liability as barriers to recommending extended use.1PubMed Central. Offering extended use of the contraceptive implant via an implementation science framework: a qualitative study of clinicians’ perceived barriers and facilitators The FDA label change should help resolve that hesitation, though some providers may still be unaware of the update or uncomfortable recommending the full five years. If your provider suggests replacing at three years, it is reasonable to ask whether the updated label changes that recommendation for your situation.