The contraceptive implant is a small, flexible rod, about the size of a matchstick, designed as a long-acting birth control method. Typically inserted just under the skin of the upper arm, it releases hormones to prevent pregnancy. While highly effective, it is possible, though rare, for the implant to move from its initial insertion site.
Understanding Implant Migration
Implant migration refers to the movement of the contraceptive device from its original placement within the arm. This movement can be minimal, just a few millimeters, or in uncommon instances, more significant, extending several centimeters. In rare cases, the implant might even travel to distant areas of the body, such as the chest wall or into blood vessels leading to the pulmonary artery. Significant migration, defined as movement of 2 centimeters or more, remains a rare occurrence, particularly if the initial insertion was performed correctly.
Reasons for Movement
Several factors can contribute to implant migration. A primary reason is improper insertion technique, such as placing the implant too deeply or at an incorrect angle. When inserted too deep, especially near blood vessels or nerves, the risk of migration increases. Newer implant designs aim to minimize incorrect placement. Individual anatomical variations, like differences in subcutaneous tissue or muscle structure, or having particularly thin arms, can also influence how the implant settles. Trauma, strenuous activity, or significant changes in body weight, such as weight loss, may also contribute to movement.
Potential Implications of Migration
When a contraceptive implant migrates, the primary concern often revolves around the difficulty of its removal. A moved implant can be challenging to locate and extract, potentially requiring more complex procedures than a standard removal. Specialized tools, different surgical approaches, or even general anesthesia might be necessary for safe extraction. While the implant is designed to deliver hormones systemically, significant migration rarely impacts hormone absorption, as the device continues to release hormones as long as it is intact. In rare instances, migration into or near major nerves or blood vessels can lead to localized symptoms such as pain, numbness, or tingling. In very rare cases of migration to the pulmonary artery, individuals might experience chest pain or shortness of breath.
What to Do if You Suspect Movement
Regularly check the position of your contraceptive implant by gently feeling for it under the skin of your upper arm. You should be able to feel both ends of the small rod. If the implant feels like it is in a different spot, is no longer palpable, or if you experience new pain, numbness, or tingling in the arm, these could be signs of migration. If you suspect your implant has moved, contact a healthcare provider or clinic promptly for advice. They can assess the situation and determine the next steps. Do not attempt to move or remove the implant yourself, as this can cause injury or make professional removal more difficult.
Locating and Removing a Migrated Implant
Healthcare providers use various methods to locate a migrated implant. Initial attempts involve careful palpation; if unsuccessful, imaging techniques like ultrasound are used. Current implants, such as Nexplanon, are radiopaque and visible on X-rays if ultrasound fails. For challenging cases, CT or MRI scans may pinpoint the exact location. Once located, removal is more complex than routine, potentially requiring specialized surgical techniques, different approaches, or referral to a specialist surgeon, especially if deep or near sensitive structures. All removals must be performed by a trained healthcare professional to ensure safety.