Why Does My Nexplanon Hurt? Causes & When to Worry

Some soreness around your Nexplanon implant is normal in the days after insertion, but pain that persists, spreads, or changes character can signal that something beyond routine healing is going on. The implant sits just under the skin of your inner upper arm, and the most common reasons it hurts range from simple bruising to rarer complications like nerve compression, deep placement, or migration into muscle tissue. Understanding the difference between expected discomfort and a genuine warning sign helps you decide whether to wait it out or call your provider.

Normal Post-Insertion Soreness

The insertion itself involves a small needle-like applicator that slides the rod beneath the skin after a local anesthetic numbs the area. A pilot study measuring pain during the procedure found that, on average, adolescents reported very low pain scores during the actual implant placement, with most of the discomfort coming from the lidocaine injection rather than the rod going in. Once the anesthetic wears off, bruising, tenderness, and mild swelling around the insertion site are expected and can last a week or two. A pressure bandage is usually applied for the first day, and a small adhesive strip stays on for several days to keep the wound closed.

During this initial healing window, the area can feel sore to the touch, and you might notice a bruise that spreads a few centimeters from the site. This is standard and does not mean the implant was placed incorrectly. Most people find that over-the-counter pain relievers and avoiding heavy lifting with that arm for a couple of days are enough to manage it. If, however, the pain is getting worse rather than better after the first week, or if the bruise is expanding and your arm feels tight and swollen, those are reasons to check in with whoever placed the implant.

Deep Placement and Why It Matters

Nexplanon is designed to sit in the subdermal space, the thin layer of fat just beneath the skin. You should be able to feel the rod by pressing gently on your inner arm. When it ends up deeper than intended, sitting within or below the layer of connective tissue called fascia, or even inside a muscle, the risk of ongoing pain goes up significantly. A large observational study found that incorrect insertion, including deep placement, occurred at a rate of roughly 13 per 1,000 insertions.¹ That’s uncommon but not vanishingly rare, and it’s one of the first things your provider should assess if your pain seems disproportionate or lingers beyond the normal healing period.

A deeply placed implant can press against or irritate structures it was never supposed to be near, including nerves, blood vessels, and muscle fibers. A systematic review of problematic removals found that subfascial and intramuscular implants were a key feature in cases referred to surgeons for extraction, often because the rod had settled close to major peripheral nerves.² If you cannot feel the rod under your skin at all, that’s a strong clue that it may be too deep, and you should let your provider know.

Nerve Compression and Neuropathic Pain

Your inner upper arm is home to several important nerves, most notably the ulnar nerve and the medial cutaneous nerves. When the implant ends up near one of these, or when swelling pushes tissue against them, the result can be pain that feels very different from a bruise. Shooting, burning, or electric-shock sensations, numbness in the forearm or fingers, and tingling that follows a specific path down the arm are all signs of nerve involvement. Pins-and-needles and numbness in the arm, hand, or fingers were actually the most commonly reported patient events in the large NORA study.¹

One case report documented a patient who developed shooting pain along the ulnar nerve distribution, including paresthesia in the hand and forearm, with the implant ultimately found lying within the perineurium of the nerve itself.³ That’s an extreme case, but it illustrates why nerve-type pain should not be dismissed. Even without direct contact, subclinical edema, meaning swelling too subtle to see with your eyes, can compress nearby nerves and produce diffuse neuropathic symptoms that are hard to pin down. A case report analyzing this mechanism suggested that the inflammatory response to the implant itself may drive this kind of nerve compression in some people.⁴

The distinction matters for you practically. Aching or bruise-like pain concentrated at the insertion site is one thing. Pain that travels, that shoots down toward your elbow or hand, or that comes with numbness or weakness in your fingers is qualitatively different and warrants a prompt call to your healthcare provider rather than a “wait and see” approach.

Migration Into Muscle or Beyond

In rare cases, the implant does not stay where it was placed. Migration means the rod moves away from the original insertion site, sometimes into the biceps muscle, sometimes further toward the axilla (armpit), and in very rare reported cases even into the chest. A case report documented a Nexplanon implant that migrated into the biceps brachii muscle, requiring surgical removal, and noted that implants which become non-palpable should be immediately imaged to prevent nerve or vascular injury.⁵ Another case reported a rod that traveled all the way to the patient’s armpit after insertion.⁶

Migration does not always cause pain right away. In one documented case, a patient had the implant placed three years prior and only noticed the problem when she could no longer feel it under her skin. Imaging revealed the rod had migrated deeper and more proximally, and surgical exploration found it resting directly on the ulnar nerve.⁷ That means pain from migration can appear months or years after insertion, often preceded by the inability to feel the rod. If you used to be able to palpate your Nexplanon and now you can’t, even if it doesn’t hurt yet, that’s worth reporting.

The exact mechanism behind why some implants migrate is not fully settled. Deep initial placement is a likely contributor, but muscle movement over time and the body’s tissue remodeling both play a role. The important takeaway is that migration-related pain tends to show up as new-onset discomfort that does not match the original insertion site, and it often involves nerve symptoms because the rod has settled near neurovascular structures it was never supposed to contact.

Fibrotic Tissue Encasement

Your body treats the implant as a foreign object, and part of the normal healing response involves forming a thin capsule of scar-like tissue around the rod. For most people, this fibrous sheath causes no problems and actually helps anchor the implant in place. But in some cases, the tissue buildup becomes excessive enough to cause discomfort, particularly a sensation of tightness or a hard lump around the implant that feels different from what you were told to expect.

The NORA study identified fibrotic tissue encasement as the most common challenge reported by clinicians during implant removal.¹ That doesn’t mean heavy scarring is frequent, but it does mean your provider is aware of this possibility. From a pain standpoint, fibrosis itself can generate a pulling or pressure sensation, especially when you extend or flex the arm, because the stiffened tissue doesn’t stretch the way normal fat and skin do. If you notice the implant area feels increasingly firm or restricted over time, or if there’s a new ache that correlates with arm movements, fibrosis could be the reason.

Localized Pain Versus Widespread Symptoms

Most Nexplanon-related discomfort stays local: soreness, tenderness, or a bruise-like feeling concentrated near the rod. Nerve irritation along a specific path, like the ulnar nerve running toward the ring and little fingers, is less common but still anatomically explainable. What catches both patients and clinicians off guard is diffuse neuropathic pain that doesn’t follow a single nerve track. One case report documented a patient with widespread, hard-to-characterize nerve symptoms after Nexplanon placement and proposed that subtle, clinically undetectable edema compressing multiple small nerve branches, combined with an inflammatory response, could explain these atypical presentations.⁴

This is worth knowing because if your arm pain is vague, widespread, or doesn’t seem to track along a textbook nerve path, it doesn’t mean you’re imagining things. It may mean the mechanism is inflammatory rather than mechanical. The practical consequence is the same: your provider needs to hear about it, and imaging or a referral may be appropriate.

How Providers Find Out What’s Going On

If your Nexplanon hurts and the cause isn’t obvious on physical exam, imaging is the next step. Ultrasound is the standard first-line tool for locating the implant and determining how deep it sits. It’s quick, painless, and accurately finds the rod in the vast majority of cases. If ultrasound doesn’t locate it, or if the implant appears to have migrated to a deeper or unusual position, MRI offers more detailed visualization, especially for implants that have settled near muscles or nerves. A review of imaging techniques for non-palpable contraceptive implants confirmed this stepwise approach, with plain X-ray serving as a backup and MRI reserved for cases where ultrasound falls short.⁸

Nexplanon contains barium sulfate specifically so it shows up on X-ray, which is a design improvement over older implants. If you’re told your implant can’t be felt and your provider orders imaging, it’s a routine step, not an emergency. The imaging helps determine whether the rod is in a safe position, has migrated somewhere problematic, or is wrapped in enough fibrotic tissue to complicate removal.

When Pain Should Prompt a Same-Day Call

Some symptoms call for urgent attention, not because they’re always dangerous, but because early action prevents complications from getting worse. You should contact your provider promptly if you experience any of the following:

Nerve symptoms: Tingling, numbness, or shooting pain that extends from the implant site toward your hand or fingers, especially along the pinky-side of your hand. One well-documented case involved ulnar nerve palsy that required surgical repair because early referral was delayed.⁹
Non-palpable implant: You can no longer feel the rod under your skin, especially if this is a change from before. A rod you can’t feel may have migrated deeper.
Worsening pain after the first week: Post-insertion pain should improve over days, not get worse. Escalating pain suggests the implant may be irritating a nerve or sitting too deep.
Signs of infection: Increasing redness, warmth, swelling at the site, pus, or fever. While insertion-site infections are uncommon, they do happen.
Arm weakness: Difficulty gripping or loss of strength in the hand or forearm could indicate nerve damage that needs evaluation.

The recurring theme in the clinical literature on Nexplanon complications is that prompt diagnosis and early referral make outcomes dramatically better. Nerve injuries that are caught and addressed quickly have much better recovery prospects than ones that go unrecognized for months.

Pain Related to Removal

If your Nexplanon is approaching its expiration date or you want it taken out, removal itself can sometimes be a source of new pain. Routine removals, where the implant is easily palpable and sitting right under the skin, tend to be quick and well-tolerated under local anesthesia. Difficulty arises when the rod has migrated, is deeply placed, or is heavily encased in fibrotic tissue.

Attempts to remove a deep or migrated implant in an office setting, without proper imaging or surgical tools, carry a real risk of nerve injury. A case report described a 21-year-old woman who suffered ulnar nerve palsy after an in-office attempt to remove a deeply implanted Nexplanon, ultimately requiring surgical exploration, excision of a neuroma that had formed, and nerve grafting to repair the damage.⁹ The systematic review of surgeon referrals for problematic extractions confirmed that implants which had already been subjected to previous removal attempts were more likely to need surgical intervention.²

What this means for you: if your provider has trouble locating or removing the implant, it is genuinely better for them to stop and refer you to a specialist with imaging guidance than to keep trying. This is not a failure; it’s the standard of care for a rod that isn’t cooperating. If you’re having pain before removal and suspect the implant is deep or has moved, mention it beforehand so your provider can plan accordingly rather than discovering the problem mid-procedure.

Pain That Sticks Around After the Implant Is Out

Most people feel immediate relief once a problematic Nexplanon is removed, but in cases where nerve damage occurred, either from the implant’s position or from the removal process itself, pain can persist. The case involving ulnar nerve palsy from an in-office removal attempt is a sobering example: the patient required sural nerve cable grafting, a procedure where a section of a sensory nerve from the lower leg is used to bridge the gap in the damaged ulnar nerve.⁹ Recovery from nerve grafts is slow and incomplete, and residual numbness or weakness can remain.

These severe outcomes are rare. They come up in the medical literature precisely because they’re unusual enough to warrant a published case report. But they underscore why nerve-type symptoms around a Nexplanon should be taken seriously from the start: the earlier a problem is identified, the less likely it is to escalate to the point where surgical repair is needed.

Common Misconceptions About Nexplanon Pain

One widespread belief is that the implant itself releases something that causes arm pain, as though the hormone leaking from the rod irritates surrounding tissue. Nexplanon releases etonogestrel, a synthetic progestin, in very small daily amounts absorbed into the bloodstream. The rod’s outer surface is biocompatible plastic. Pain from Nexplanon is mechanical or inflammatory, not hormonal in origin. The rod pressing on something it shouldn’t, tissue swelling in response to a foreign body, or scar tissue forming around it are the actual culprits.

Another misconception is that if the implant can be felt in the right spot and the insertion site looks fine, it can’t be causing nerve problems. Edema-induced nerve compression can happen even when the implant appears properly positioned, because the swelling affects tissue around the rod rather than requiring the rod itself to touch a nerve directly.⁴ A provider who examines you, confirms the implant is palpable, and says everything looks normal may be correct about placement but still missing an inflammatory process that’s affecting nearby nerves.

Finally, some people worry that having the implant removed early will somehow be medically complicated or that they’ll be pressured to keep it. If your Nexplanon is causing you persistent pain, you have every right to have it taken out regardless of how long it’s been in place. Removal is typically straightforward for properly placed implants, and your provider can discuss alternative contraceptive options at the same visit.