How do I check the placement and effectiveness of a birth control implant (e.g., Nexplanon)?

How to Check Birth Control Implant Placement

Immediately after insertion, both you and your healthcare provider should verify the implant is in place by palpating (feeling) it under the skin of your upper arm. 1

Immediate Post-Insertion Verification

The most critical check occurs right after insertion:

• Both patient and provider should palpate the implant together immediately after the procedure to confirm proper placement 1
• The implant should be easily felt as a small rod just under the skin on the inner side of the non-dominant upper arm, approximately 6-8 cm above the elbow 2
• If you cannot feel the implant immediately after insertion, it may not have been inserted at all, or it may have been inserted too deeply 1

Ongoing Self-Checks

You should be able to feel your implant at any time during the 3 years of use:

• Gently palpate the inner aspect of your upper arm where the implant was placed
• You should feel a small, firm rod approximately 4 cm long under your skin
• If at any time you cannot feel the implant, contact your healthcare provider immediately and use backup contraception (such as condoms) until proper placement is confirmed 1

When the Implant Cannot Be Felt

If the implant is non-palpable, several imaging methods can locate it:

First-Line Imaging

• Ultrasound is the recommended first-line imaging modality for locating non-palpable implants 3, 4
• Standard ultrasound or newer handheld ultrasound devices can reliably detect the implant 3
• The implant appears as an echogenic (bright) focus on ultrasound 3

Second-Line Imaging

• X-ray can locate Nexplanon (but not the older Implanon), as Nexplanon contains barium sulfate making it radiopaque 2, 5
• If the implant cannot be found in the arm, chest X-ray or CT may be needed, as rare cases of migration to blood vessels (including pulmonary arteries) have been reported 1, 6

Critical Safety Points

Common pitfalls to avoid:

• Never attempt removal if the implant cannot be palpated—it must first be localized with imaging 4, 7
• Deep insertion increases difficulty with both localization and removal, potentially requiring surgery 1
• Weight gain can make a previously palpable implant harder to feel, but this doesn't mean it has migrated 4
• The implant may not have been inserted at all if it was never palpable after the initial procedure 1

Effectiveness Verification

The implant's contraceptive effectiveness does not require routine checking beyond confirming it's in place:

• Pregnancy rate is less than 0.05% per year with proper placement 8
• Effectiveness remains high even in women with overweight or obesity 9
• Use backup contraception immediately if you cannot feel the implant until your provider confirms proper placement 1

The implant is approved for 3 years of use, though evidence suggests effectiveness may extend to 4 years 10. Track your removal date and schedule an appointment on or before that date 1.