Levonorgestrel vs. Copper Intrauterine Devices for Emergency Contraception

In this RCT (n=711 randomised; 638 received treatment and had 1-month outcome data), the levonorgestrel IUD was non-inferior to the copper IUD, with a positive pregnancy test in 0.3% v 0% (between-group difference of 0.3%; 95% CI -0.9 to 1.8%; below pre-specified margin of 2.5%).

Source:

New England Journal of Medicine