Abstract： Objective To investigate the perinatal outcome of fetus with increased nuchal translucency (NT) at first trimester.Methods The thickness of NT above 95th percentile of the fetuses with same crown-rump length (CRL) was set as the criteria of increased NT.The outcomes of fetuses with increased NT during early pregnancy from Jan.2008 to Dec.2009 in Guangzhou Women and Children's Medical Center were followed up.The information of ultrasound at second trimester,pregnant complications and delivery outcome were collected.All infants were followed up for 3 months after birth and were divided into four groups according to their different thickness of NT.The relationship between NT thickness and perinatal outcome were analyzed with single factor analysis of variance and multiple comparison method.Results Among the 178 cases we followed up,there were 2 spontaneous fetal losses and 19 terminations whose reasons were Down syndrome (n=6),severe a thalassemia (n =5),fetal malformations (n =7) and social factor (n =1).Among the 157newborns delivered,one was found with congenital heart disease.The rate of abnormal infants was 11.8％ (21/178) and the detection rate of abnormal infants was 9 5.2％ (20/21).Healthy living rate of fetus with NT thickness between 95th percentile and 2.9 mm was 96.1％ (122/127); 82.4％ (28/34) for those with NT thickness between 3.0 mm and 3.9 mm; and 35.3％ (6/17) when NT≥ 4.0 mm.Conclusions Increased NT might have close relationship with poor pregnant outcome.The thicker the NT,the lower the healthy living rate of the fetus.The pregnant outcome is very poor if NT≤4.0 mm.