Migration of Implanon

To determine whether or not migration of the Implanon rod does occur if correctly positioned and, if indeed migration does occur, to measure the degree of such migration.

A prospective study of 100 women who requested and had Implanon rods inserted by one fully trained health care professional holding the Faculty of Family Planning and Reproductive Health Care Letter of Competence in Subdermal Contraceptive Implant Techniques. Measurements were made from the insertion site to the distal end of the rods at 3 and 12 months post-insertion.

Of the 100 women studied, 95 were seen for follow-up at 3 months. There was no migration of Implanon in 58 (61%) patients. Of the remaining 37 (39%) patients where migration had occurred, 34 showed migration caudally and only three demonstrated cranial migration. With regard to the degree of migration, all but one case showed this to be less than 2 cm either cranially or caudally. At 1-year follow-up 87 patients were seen. No migration was noted in 39 (45%) patients. In the remaining 48 (55%) patients where migration had occurred, 44 showed migration caudally and only four demonstrated cranial migration, which in one case was over 2 cm. With regard to the degree of migration, all but one case showed this to be less than 2 cm either cranially or caudally. The measurement in the single case showing migration over 2 cm at 3 months remained the same at the 1-year follow-up.

These results show that up to 1 year after insertion of Implanon significant migration of the rod does not occur. The degree of migration noted in all cases except one was less than 2 cm. Where migration was noted, in the majority of cases this occurred caudally towards the insertion site. There were no cases of deep migration.