There is growing advocacy for use of long-acting reversible contraception among sexually active adolescents. Our primary aims were to evaluate the etonogestrel subdermal contraceptive implant (SCI) insertion trends among adolescents, as well as SCI retention at 1, 2, and 3 years, indications for removal, and to identify pregnancies that occurred during SCI use.

A retrospective cohort study was conducted of adolescents aged 13-19 years with SCI insertions in 2008-2014 within a large integrated health care system. Demographic and clinical characteristics included age, race/ethnicity, body mass index, gravidity, parity, insertions, reinsertions, indications for removal, and pregnancy. Electronic medical record review was conducted on a randomized sample of 540 adolescents with insertions during 2008-2011 for the retention objective to validate electronically extracted variables. Analyses included descriptive statistics, survival analysis with Kaplan-Meier estimates for implant retention and Cochran-Armitage trend test for insertions according to year during 2008-2014.

Most adolescent SCI users were non-Hispanic white (43%), or Hispanic (34.2%) and 16 years or older (84.2%) at the time of insertion. Overall, 1-, 2-, and 3-year retention rates were 78.6%, 59.4%, and 26.2%, respectively, with retention at 44.3% at 2 years 9 months (indicative of removal of method for near expiration of 3-year device). The insertion rate trend showed statistically significant increases annually, from 0.14% in 2008 to 0.91% in 2014; P < .0001. No pregnancies were documented during implant use. The most common indication for SCI removal was device expiration.

SCI insertions increased annually among adolescents, with more than a sixfold increase over the 6-year study period, and more than half of the SCIs were retained through 2 years of use. The most common indication of SCI removal was completion of Food and Drug Administration-approved duration.