title: A multicentre efficacy and safety study of the single contraceptive implant Implanon. Implanon Study Group.
abstract: An open, multicentre study was performed to assess efficacy, safety and acceptability of the single-rod contraceptive implant Implanon. The study involved 635 young healthy women, who were sexually active and of childbearing potential. The women were followed up every 3 months over the entire study period. Originally the study was designed for 2 years, but was extended to 3 years in a group of 147 women from two centres. Altogether, 21 centres in nine different countries participated. The average age of the women was 29 years (range 18-42 years), of whom 83.5% had been pregnant in the past. No pregnancy occurred during treatment with Implanon, resulting in a Pearl Index of 0 (95% confidence interval: 0.0-0.2). In the first 2 years, 31% had discontinued the treatment. Of the 147 women in the study extension, nine discontinued (6%) treatment. Bleeding irregularities was the main reason for discontinuation during the first 2 years of use (17.2%) and adverse experiences in the third year (3.4%). Implant insertion and removal were fast and uncomplicated in the vast majority (97%) of cases. Return of fertility was prompt. In conclusion, Implanon has excellent contraceptive action during its lifetime of 3 years. The safety profile is acceptable and not essentially different from progestogens in general.
authors.affiliation: Chilean Institute of Reproductive Medicine, Santiago, Chile.
authors.forename: H B
authors.initials: HB
authors.lastname: Croxatto
authors.forename: J
authors.initials: J
authors.lastname: Urbancsek
authors.forename: R
authors.initials: R
authors.lastname: Massai
authors.forename: H
authors.initials: H
authors.lastname: Coelingh Bennink
authors.forename: A
authors.initials: A
authors.lastname: van Beek
mesh_terms: D000293:Adolescent; D000328:Adult; D003271:Contraceptive Agents, Female / Q000008:administration & dosage* / Q000009:adverse effects*; D017135:Desogestrel; D005260:Female; D006801:Humans; D015918:Infusion Pumps, Implantable / Q000009:adverse effects*; D011247:Pregnancy; D016896:Treatment Outcome; D014592:Uterine Hemorrhage; D014753:Vinyl Compounds / Q000008:administration & dosage* / Q000009:adverse effects*
chemical_list: D003271:Contraceptive Agents, Female; D014753:Vinyl Compounds; C044815:etonogestrel; D017135:Desogestrel