1. Kavanaugh ML, Jerman J (2018) Contraceptive method use in the United States: trends and characteristics between 2008, 2012 and 2014. Contraception 97:14–21
2. United Nations Population Fund (2016) TCu380A intrauterine contraceptive device (IUD) WHO/UNFPA technical specification and prequalification guidance. United Nations Population Fund, NY, USA
3. World Health Organization (ed) (2009) Medical eligibility criteria for contraceptive use – 4th ed. World Health Organization, Geneva
4. United Nations Department of Economic and Social Affairs (2011) World contraceptive use 2011. United Nations Department of Economic and Social Affairs, NY, USA. Available via
http://www.un.org/esa/population/publications/contraceptive2011/wallchart_front.pdf
. Accessed 01 Aug 2018
5. Dietrich O, Reiser MF, Schoenberg SO (2008) Artifacts in 3-T MRI: physical background and reduction strategies. Eur J Radiol 65:29–35