Abstract: Objective To investigate the ultrasonographic indicators predicting the outcomes of selective fetal growth restriction (sFGR) fetuses in monochorionic twins under expectant management. Methods Monochorionic twins with sFGR diagnosed in the First Affiliated Hospital of SUN Yat-sen University from Jan.2005 to May 2010 were included into this study.All patients underwent expectant treatment.Ultrasound appearances of monochorionic twins were documented in detail when sFGR was diagnosed.At the initial evaluation,presence or absence of the following abnormalities were documented, including abnormal Doppler flow in the umbilical artery,polyhydramnios in the larger twin,oligohydramnios,fetal weight discordance and velamentous cord insertion in sFGR fetuses; gestational age at diagnosis was recorded as well.The relationship between these ultrasound characteristics and mortality of sFGR fetus was analyzed with Logistic regression.Results Of 51 sFGR fetuses,11 (21.6%) suffered from fetal death,including four intrauterine demise and seven neonatal deaths both twins were dead in 3 cases. Logistic regression analysis demonstrated that oligohydramnios (OR=22.80,95%CI:3.58-145.31,P=0.001) and abnormality of diastolic flow in the umbilical artery (OR=6.51,95%CI:1.16-36.53,P=0.033) were independent risk factors of mortality of sFGR fetuses. Conclusions Both oligohydramnios and abnormal Doppler flow in the umbilical artery suggest poor prognosis of sFGR fetuses in monochorionic twins.