Shoulder Contraceptive Implant Study
Condition: Contraception
Study type: Interventional
Phase: Phase 4

Summary: 
      This study will be the first to establish pharmacokinetic curves for the etonogestrel
      contraceptive implant with scapular subdermal insertion. By obtaining this pharmacokinetic
      data, the investigators can compare this data to already published pharmacokinetic data with
      conventional implant insertion. This comparison can provide some reassurance that the
      absorption and distribution of etonogestrel from the contraceptive implant with scapular
      insertion is similar to that found with conventional insertion. With similar pharmacokinetic
      properties, the investigators would expect scapular insertion of the implant to maintain
      similar contraceptive efficacy for the populations of women that may benefit from this
      alternative insertion site. Preliminary safety data will also enrich the understanding of any
      potential insertion site side effects with subdermal scapular implant insertion, as the
      investigators currently only have a single case report with side effect outcomes. The
      investigators can then use this pilot data to support future larger investigations on
      subdermal scapular implant insertion given its complete avoidance of the neurovascular
      complications associated with arm insertion.
    

Detailed description: 
      The etonogestrel contraceptive implant (Nexplanon®) remains the most effective hormonal
      contraceptive method available in the U.S. The contraceptive implant is routinely inserted
      just beneath the skin on the inner-side of the non-dominant arm, but insertion at this site
      has resulted in rare, yet potentially morbid complications. These complications are due to
      the close proximity of major neurovascular structures (e.g. basilic vein, ulnar nerve) in the
      sulcus between the biceps and triceps muscles. Insertion of the implant deep in the arm has
      resulted in severe complications including migration of the implant into the pulmonary
      vasculature and neurological injury at the time of implant removal. Though these
      complications are rare, their report directly led to changes in the manufacturer's mandatory
      insertion training to move the implant insertion site inferiorly, though it is unlikely that
      this change will completely remove the risk of these rare insertion complications.

      In addition to the rare complications of deep implant insertion in the arm, patients with
      specific medical conditions are also not ideal candidates for this standard insertion site.
      Patients with psychotic illnesses or development delays often require reliable contraception,
      but the arm insertion site for the implant is easily accessible and injuries can result from
      self-removal attempts among these patients. Furthermore, patients with muscular dystrophy
      disorders may not have adequate tissue in this region of the arm to buffer the implant from
      the underlying neurovascular structures. In order to address the needs of these patient
      populations, insertion of the contraceptive implant at an alternative subdermal scapular site
      has been reported in the literature. This insertion just beneath the skin overlying the
      inferior edge of the scapula represents an ideal alternative location for the contraceptive
      implant due to its location far from danger zones of neurovascular structures,
      inaccessibility to patients with mental illnesses, and underlying bony structure preventing
      unintentional deep insertion. However, more data are needed regarding the rate of drug
      absorption and overall safety with etonogestrel implant insertion at this alternative site.

      The study will address this knowledge gap by piloting contraceptive implant insertion at this
      alternative scapular site among five healthy, reproductive aged women. The investigators will
      insert contraceptive implants at this alternative scapular site and conduct serial
      measurements of the amount of drug (etonogestrel) circulating in each participant's system
      over the course of one year. These measurements will allow us to compare the amount of
      circulating drug from the contraceptive implant between this alternative insertion site and
      the already published amounts found with standard insertion in the arm. The investigators
      will also ask participants about any insertion site related side effects and also general
      implant-related side effects (e.g. abnormal bleeding, headaches, weight gain) during the
      course of the study. This will provide preliminary side effect data to help us better
      understand patient experience with this alternative insertion site. Ultimately, the
      investigators hypothesize that this study will provide reassuring data that can support
      future larger investigations on this alternative scapular insertion site for the implant.
      This alternative insertion site may allow patients who otherwise are not currently candidates
      for the most effective hormonal contraceptive method to uptake contraceptive implants in a
      safe manner. This research will also allow healthcare providers to discuss an alternative
      site for the contraceptive implant for those patients concerned about the potential risks of
      deep arm insertion, thus improving patient-centered options for contraceptive implant
      provision.
    

Intervention name(s): Etonogestrel implant
Intervention type(s): Drug
Intervention description(s): Insertion of the contraceptive implant at an alternative insertion site located over the scapula
Intervention MeSH terms: Etonogestrel
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Basic Science