Chen Melissa J, Kim Caron R, Whitehouse Katherine C, Berry-Bibee Erin, Gaffield Mary E
Department of Obstetrics and Gynecology, University of California, Davis, Sacramento, CA, USA.
Department of Reproductive Health and Research, World Health Organization, Geneva, Switzerland.
Int J Gynaecol Obstet. 2017 Feb;136(2):113-119. doi: 10.1002/ijgo.12064. Epub 2016 Dec 13.