Piriyev, E., & Romer, T. (2020). Pregnancy while using a levonorgestrel-releasing intrauterine system 52 mg: a case report. International Journal of Reproduction, Contraception, Obstetrics and Gynecology, 9(11), 4692–4694. https://doi.org/10.18203/2320-1770.ijrcog20204835