Switching and discontinuation of participant-masked randomization to a copper or levonorgestrel intrauterine device when presenting for emergency contraception

Abstract

Objectives: Examine intrauterine device (IUD) switching or discontinuation up to 6 months after participant-masked randomization to different IUDs.

Study design: Participants were randomized 1:1 to the copper T380A or levonorgestrel 52 mg IUD for emergency contraception and informed they could switch IUD type without cost at any time.

Results: Of the 327 subjects allocated to the levonorgestrel IUD, 7 (2.1%) switched their IUD type by 6 months versus 18 (5.5%) of the 328 copper IUD users (RR: 0.4 [95% CI: 0.2, 0.9], p = 0.03). Six-month IUD discontinuation occurred in 34 (10.4%) levonorgestrel and 35 (10.7%) copper IUD users.

Conclusion: Individuals randomly assigned to IUD type at presentation for emergency contraception continue their assigned IUDs at high rates over 6 months.

Implications: While many recruited individuals declined enrollment, those who accepted randomization had high continuation rates; the high continuation and low cross-over supports using IUD randomization as a tool for future investigation. Participants' similar rates of and reasons for switching and discontinuation by IUD type over the study period may impact clinical counseling.

Keywords: Contraception; Intrauterine device; Long acting reversible contraception; Randomization; Randomized controlled trial.