Related Experiment Video
Updated: Feb 13, 2026

Multimodal Protocol for Assessing Metacognition and Self-Regulation in Adults with Learning Difficulties
Published on: September 27, 2020
Factors associated with removal difficulties of etonogestrel-containing contraceptive implants (Nexplanon®)
Julien Chevreau1, David Krief1, Osama Abou Arab1
1Amiens-Picardie University Hospital, France.
Objectives:
Nexplanon®'s new applicator system was designed to limit deep implant placements, known to lead to difficult removals. However, removal difficulties still exist and induce specific and potentially severe complications. Our objective was to identify risk factors associated with difficult removals.
Study Design:
A retrospective single-center study was performed from January 2015 to December 2016. Participants were divided into two groups depending on whether implant was removed during a standard ("standard removal" group) or difficult consultation ("difficult removal" group) after an initial failed removal attempt.
Results:
The difficult and standard removal groups comprised 63 and 660 women, respectively. In a univariate analysis, significant intergroup differences were found for weight gain (3.7 ± 7.3 kg in the difficult removal group vs. 1.3 ± 5.1 in the standard removal group), proportion of placements performed in private practice (66.7% vs. 19.8%, respectively), and duration of Nexplanon® placement (29.4 ± 11.3 months versus 26 ± 13.6, respectively). We also reported more frequent sub-brachial fascia placements when Nexplanon® was implanted by a private practitioner (7.5% cases versus 0.4% in hospital implantations, p < 0.001). In a stepwise binary logistic regression analysis, placement by a private practitioner, weight gain >1 kg since placement, and duration of implant placement >25 months were confirmed as independent risk factors for removal difficulties (respective risk ratios 7.63 [95% IC 4.35-13.33], 2.10 [1.18-3.70], and 1.91 [1.06-3.44], p < 0.05).
Conclusions:
Awareness of these three simple parameters might help physicians to identify "at risk-patients", and suggest a specific consultation before risking a potentially hazardous removal (with its associated, specific morbidity). Our results also emphasize importance of training in implant insertion.
Related Concept Videos
Transcription Factors
Factors Affecting Solubility
Transcription Elongation Factors
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA...
Factors Affecting Drug Distribution: Miscellaneous Factors
Age plays a significant role due to differences in body composition among different age groups. Infants, for instance, have a higher proportion of total body water and lower albumin levels, a protein that binds drugs in the bloodstream. This unique composition in infants enhances the...
Electrolytes: van't Hoff Factor
The colligative properties of a solution depend only on the number, not on the identity, of solute species dissolved. The concentration terms in the equations for various colligative properties (freezing point depression, boiling point elevation, osmotic pressure) pertain to all solute species present in the solution. Nonelectrolytes dissolve physically without dissociation or any other accompanying process. Each molecule that dissolves yields one...
Factors Affecting Protein-Drug Binding: Drug-Related Factors
One crucial factor in drug-protein binding is the drug's lipophilicity or its affinity for fat. More lipophilic drugs tend to have higher binding extents. For example, highly lipophilic drugs like cloxacillin exhibit substantial protein binding, with as much as 95% of the drug binding to proteins. In...

