2448-8909 2448-8909 S2448-89092016000300209 México México 00 08 2016 00 08 2016 30 3 209 210 1 Society of obstetricians and gynaecologist of Canada (SOCJ) 2001 102 1-35 2 2012 55 1 1 324-35 3 2010 39 4 4 267-75