Nexplanon Pain Months Later: Causes & When to Worry

Pain at the Nexplanon site weeks or months after insertion is uncommon but not unheard of, and it usually traces to a handful of identifiable causes ranging from lingering tissue inflammation to rare complications like nerve compression or implant migration. Complications with the implant occur in roughly 0.3% of insertions, and most involve self-resolving bruising, swelling, and soreness from the insertion itself.¹ But when discomfort persists or changes character well after the insertion wound has healed, the explanation is usually more specific and worth investigating.

Why Some Soreness Lingers After the Insertion Heals

Nexplanon sits just below the skin on the inner side of your upper arm, in a zone packed with soft tissue, small blood vessels, and sensory nerves. The insertion itself causes minor trauma: the applicator needle creates a tract through the skin and subcutaneous tissue, and some bruising and tenderness afterward is expected. For most people, that soreness fades within a couple of weeks. When it stretches into months, the usual suspect is a low-grade inflammatory response around the implant. Your body recognizes the rod as a foreign object and walls it off with a thin capsule of fibrous tissue. In some people, this process produces enough local swelling to press on nearby sensory nerves, creating an aching or burning sensation that persists well beyond the initial healing window.

A case report in Cureus documented exactly this pattern. A patient returned two months after insertion reporting persistent discomfort, decreased sensation, and tingling in the arm that worsened with movement or when the area was touched. Examination showed tenderness over the implant site and slightly reduced grip strength.¹ The authors attributed the symptoms to subclinical edema-induced nerve compression accompanied by an inflammatory response. In plain terms, swelling too subtle to see on the surface was squeezing nerves enough to cause real symptoms.

Nerve Compression and Neuropathic Pain

The inner upper arm contains several important nerves, including the median nerve, the ulnar nerve, and the medial antebrachial cutaneous nerve. Nexplanon is supposed to be placed in the subdermal space, well above these deeper structures. But even a correctly placed implant can cause nerve-related symptoms if the surrounding tissue swells enough. The discomfort this produces feels different from ordinary soreness. Instead of a dull ache at the insertion site, you might notice tingling, numbness, or a pins-and-needles sensation that radiates down the forearm or into the hand. Some people describe a burning quality or pain that flares with certain arm movements.

This type of nerve irritation is the dividing line between “annoying but normal” and “worth investigating.” Typical post-insertion tenderness is localized right where the rod sits and gradually improves. Neuropathic symptoms, by contrast, can spread along the path of the affected nerve, sometimes reaching the wrist or fingers. In the case described above, the patient had diffuse symptoms across the arm rather than pain confined to the implant site, which is what made the presentation atypical and prompted further workup.¹

Deep Placement and Why It Matters

One of the more significant risk factors for persistent pain is an implant that was placed too deep. Nexplanon is designed to sit in the subdermis, the layer of fat just below the skin. When it ends up beneath the fascial plane, in or near muscle tissue, it is much closer to the major nerves and blood vessels of the arm. A systematic review examining cases of inadvertently deep and nonpalpable implants found that the ulnar, median, and medial antebrachial cutaneous nerves were all at risk, and transient nerve symptoms were common after surgical removal of these deeper devices.²

A key clue that the implant may be too deep is whether you can easily feel it under your skin. You should be able to palpate the entire length of the rod by pressing gently along your inner arm. If you cannot feel it at all, or if it seems to have shortened or moved since insertion, that warrants a call to your provider. Implants that are nonpalpable should be located with imaging before anyone attempts removal, because blind exploration in the area of the brachial artery and major arm nerves can cause serious damage.³

When Implants Move

Migration is rare, but it happens. The implant can shift from its original position, sometimes traveling into the biceps muscle or settling near neurovascular structures deeper in the arm. One documented case involved a Nexplanon that migrated into the biceps brachii muscle and required surgical removal.³ Another case found a migrated implant sitting directly next to the ulnar nerve deep in the upper arm.⁴

Migration typically comes to attention because the implant becomes harder to feel, or because new symptoms appear that were not present at first. Pain from a migrated implant tends to be positional, flaring up when you use the arm in certain ways, because the rod has moved into tissue that is more mechanically active. If the implant has settled against a nerve, you might develop tingling or numbness in the hand that was not there in the first few weeks after insertion. The practical takeaway is straightforward: periodically check that you can still feel the rod in its original position. If it has become nonpalpable, get imaging done promptly to figure out where it has gone.

Allergic Reactions to the Implant Material

Nexplanon contains a small amount of barium sulfate, which is what makes the rod visible on X-ray. In extremely rare instances, someone can react to this material. One reported case involved a woman who developed a local reaction at the implant site that persisted until the device was removed. Medical treatment alone did not resolve the symptoms, but within 72 hours of removal the patient was completely asymptomatic. The authors noted that allergic reactions to barium sulfate in Nexplanon are vanishingly rare, with only two previously described cases at the time of their report.⁵

What distinguishes an allergic reaction from ordinary inflammation is the pattern. Allergic responses often involve redness, itching, or swelling that does not improve over time and may actually worsen. The skin over the implant might look different from surrounding tissue. If you had uneventful healing initially and then developed a persistent local skin reaction weeks or months later, a material sensitivity is at least worth considering, though it remains very unlikely.

Physical Damage to the Rod Itself

Nexplanon is a flexible plastic rod, and while it is designed to withstand normal daily activity, it can break. A sharp impact, vigorous contact sports, or even repeated bending stress can fracture the implant in place. One case report documented a traumatic in-situ fracture that presented as an altered feel when the patient pressed on the area, without any visible bleeding or bruising. The prescribing information notes that disruption of the implant’s structure can compromise the controlled release of its hormone, potentially leading to slightly increased hormone delivery and changes in bleeding patterns.⁶

A fractured implant can produce new pain for a couple of reasons. Broken ends may have sharper edges that irritate surrounding tissue, and the disrupted capsule of fibrous tissue around the rod can trigger a fresh inflammatory response. If the rod suddenly feels different when you check it, if you can feel what seems like two separate pieces rather than one smooth rod, or if new pain or irregular bleeding appears after a physical impact to the area, mention it to your provider.

Red Flags Worth Acting On

Most delayed Nexplanon pain falls into the “annoying but not dangerous” category. However, certain symptom patterns should prompt a timely visit rather than a wait-and-see approach:

Radiating numbness or tingling: Symptoms that travel down the forearm into the hand, especially along the ring and pinky fingers (ulnar nerve territory) or the thumb and index finger (median nerve territory), suggest nerve involvement rather than simple tissue soreness.
Grip weakness: Difficulty opening jars, dropping objects, or a noticeable decline in hand strength points to motor nerve compression, which is more urgent than sensory symptoms alone.
Nonpalpable implant: If you can no longer feel the rod under your skin, or it seems significantly shorter than before, the implant may have migrated or fractured.
Swelling or skin changes: Persistent redness, warmth, or skin thickening over the implant site weeks after insertion suggests either infection or a hypersensitivity reaction.
Worsening trajectory: Pain that was mild and is steadily getting worse over weeks or months, rather than improving, warrants investigation regardless of its character.

The case in which a patient presented two months post-insertion with decreased sensation, tingling that worsened with movement, and reduced grip strength illustrates why this symptom constellation matters.¹ These are not vague complaints; they point to a specific mechanism that can be evaluated and treated.

How Providers Locate and Remove Problem Implants

When delayed pain leads to a decision to remove the implant, the approach depends heavily on where the rod is sitting. A normally positioned, palpable implant is straightforward to take out in a clinic with a small incision. The procedure that gets complicated is removal of an implant that has migrated deep or is no longer palpable.

Imaging is the first step for any nonpalpable implant. Ultrasound is the most common starting point because it can visualize the rod and its relationship to surrounding structures in real time. A study in European Radiology found that minimally invasive removal under continuous ultrasound guidance was effective for all implant locations in their cohort, with short procedure times, small incisions, low pain levels, and no significant complications.⁷ In some cases, fluoroscopy (real-time X-ray) is used alongside ultrasound to pinpoint the implant, particularly when it has migrated into muscle. One case of a Nexplanon embedded in the biceps was successfully removed with a small incision using this combined imaging approach.⁸

The stakes of removal rise when the implant is in contact with nerves. In one severe case, surgical exploration found a Nexplanon deep to the brachial fascia, in direct contact with the ulnar nerve and less than five millimeters from the brachial artery. The ulnar nerve had been severely damaged, requiring microsurgical reconstruction with a nerve graft harvested from the patient’s lower leg to bridge a three-centimeter gap in healthy nerve tissue.⁹ This is an extreme example, and it involved a removal attempt that went wrong rather than the implant causing damage on its own. But it underscores why deep or nonpalpable implants should be referred to experienced specialists, often interventional radiologists or upper-extremity surgeons, rather than removed in a primary care office.

Pain That Is Real but Not Structural

Not all delayed arm pain with a Nexplanon in place traces to a mechanical problem with the implant. The hormonal effects of the device can cause headaches, mood changes, and generalized body aches in some users. These are systemic side effects of etonogestrel, not local complications, and they can begin or worsen months into use as hormone levels shift. The distinction matters because systemic side effects will not show up on imaging and will not be fixed by repositioning the implant. They require a conversation about whether the device is the right method for you.

There is also the possibility that arm pain after Nexplanon insertion is coincidental. Musculoskeletal issues in the upper arm, repetitive strain injuries, or even cervical spine problems can all produce symptoms that feel like they are coming from the implant area. If your provider examines the site, confirms the implant is properly positioned and palpable, and finds no signs of nerve irritation, it may be worth exploring other explanations before assuming the implant is the cause.

What Removal Feels Like and What Happens After

If your provider decides the implant should come out, the experience depends on the situation. For a routine, palpable implant, you get a local anesthetic injection, a small incision, and the rod is grasped and pulled out. Discomfort is minimal and recovery is quick, usually just a bandage for a few days. For deep or migrated implants, the procedure may involve imaging guidance, a slightly larger incision, and occasionally sedation, but even in these cases the recovery is typically straightforward when the implant has not damaged surrounding structures.

After removal, symptoms caused by the implant itself generally resolve. In the allergic reaction case mentioned earlier, the patient was symptom-free within 72 hours.⁵ Nerve compression symptoms from edema or inflammation take longer, because irritated nerves need time to heal. Mild tingling or numbness may linger for weeks to months after the source of compression is gone. In cases where actual nerve damage occurred, recovery depends on the severity. The patient in the severe case who required nerve grafting still faced a long rehabilitation, because regrowing nerve fibers through a graft is a slow biological process measured in months to years rather than days.

For people who had their implant removed due to delayed pain and want to continue using long-acting contraception, the question of whether to try another implant depends on what caused the problem. Migration and deep placement are insertion technique issues, not inherent to the device. A material allergy, on the other hand, would rule out reinsertion. Your provider can help sort through the specifics.

Checking Your Own Implant

One of the simplest things you can do is a regular self-check, something the manufacturer recommends but many people forget about after the first few weeks. Press gently along the inner side of your upper arm where the implant was placed. You should feel the entire length of the rod, roughly the size of a matchstick, just under the skin. Do this every few months. If the rod feels shorter than before, has a notch or gap in it, or you cannot feel it at all, schedule an appointment. These checks take seconds and are the earliest warning system for migration or fracture. They will not detect nerve compression or inflammatory reactions, but those problems tend to announce themselves with symptoms you would notice anyway.