32. Considerations in adolescent use of the etonogestrel subdermal implant

Abstract

<h3>Background</h3> There are many reasons for choosing the etonogestrel subdermal implant (hereafter "implant"). Limited data exists on outcomes of implant use in adolescents, and specifically, on the management of abnormal uterine bleeding (AUB). The goals of this study include characterize the purpose of implant placement in adolescents, describe rates and management of side effects, and identify reasons for early discontinuation of the implant. <h3>Methods</h3> This is a retrospective cohort study of females less than 18 years who had the implant placed from 2013-2018, identified using Current Procedural Terminology codes. Data were collected on contraceptive history, bleeding profiles, side effects, and outcomes. Descriptive statistics, analysis of variance tests, Fisher's exact test, and chi-square test data are reported. This study was IRB approved. <h3>Results</h3> A total of 272 patients were included in this study. The average age of menarche was 12 years and average age at insertion was 16 years. The majority of patients (90%) were nulliparous, 65% had been sexually active prior to implant placement, and 84% desired the implant for contraception. Of 241 patients who had at least one follow up visit, 187 reported AUB. On average, adolescents reported AUB starting 2.7 months after placement, which they managed expectantly for 10.3 months prior to desiring removal or trial of medication to resolve AUB. Of the 187 patients who reported AUB, 59% had no documented discussion of options for management and 24% had only one option offered. Trials of different medications for the treatment of AUB had varying effects on bleeding patterns (Table 1). Average time of removal for those with AUB was 22.1 months after implant placement, similar to 21.5 months for those without AUB. Most patients (76%) had the implant in place for at least 12 months. Adolescents with frequent or prolonged bleeding were more likely to have the implant removed prior to 12 months than those with other bleeding patterns (p=0.001). Patients complaining of weight gain and mood issues were also more likely to have early removal (p<0.001 and p=0.049, respectively). There was no significant difference in average percentage change in BMI between adolescents who did and did not complain of weight changes. <h3>Conclusions</h3> Adolescents mostly chose the implant for contraceptive efficacy and, although AUB was common, three-quarters chose to continue for at least 12 months. Prolonged or heavy bleeding, mood issues, and perceived weight gain were associated with earlier removal. Several options exist to treat implant-related AUB, and improved use of these medications may make bleeding patterns more tolerable. Additional studies are needed to optimize treatment of AUB and address other bothersome side effects.