Key references: Effectiveness of contraceptive method

Family Planning Alliance Australia (FPAA). How effective is my contraceptive method? Brisbane, Queensland: FPAA; 2019. https://www.familyplanningallianceaustralia.org.au/larc/
Heinemann K, Reed S, Moehner S, Minh TD. Comparative contraceptive effectiveness of levonorgestrel-releasing and copper intrauterine devices: the European Active Surveillance Study for Intrauterine Devices. Contraception 2015;91(4):280–3. https://www.ncbi.nlm.nih.gov/pubmed/25601350
Nelson A, Apter D, Hauck B, Schmelter T, Rybowski S, Rosen K, et al. Two low-dose levonorgestrel intrauterine contraceptive systems: a randomized controlled trial. Obstet Gynecol 2013;122(6):1205–13. https://www.ncbi.nlm.nih.gov/pubmed/24240244
The Faculty of Sexual & Reproductive Healthcare (FSRH) Clinical Effectiveness Unit. New product review: Kyleena 19.5 mg intrauterine delivery system. Edinburgh: FSRH; 2018 (Amended 2019). https://www.fsrh.org/documents/fsrh-ceu-new-product-review-kyleena-january-2018/
Winner B, Peipert JF, Zhao Q, Buckel C, Madden T, Allsworth JE, et al. Effectiveness of long-acting reversible contraception. N Engl J Med 2012;366(21):1998–2007. https://www.ncbi.nlm.nih.gov/pubmed/22621627