RESUMO
Objective To investigate the categories of fetal anomalies detected by ultrasound scan in the third trimester.Methods From January 1,2012 to December 31,2013,492 singleton fetuses were found to have structural abnormalities on the first,second or third trimester ultrasound scan in the Peking University First Hospital,only 50 (10.2％) fetuses were detected on the third trimester (≥ 28 weeks of gestation) with no abnormalities detected on the first and second trimester scan,were enrolled.The categories of the fetal structural abnormalities were analyzed.Results The age of the mothers of the 50 fetuses with structural abnormalities was (35.7± 5.2) years (26-43 years) with an average gestation of (32.4±2.8) weeks (28.6-36.8 weeks).These abnormalities were seen in the central nervous system (42％,21/50),digestive system (28％,14/50),urinary system (16％,8/50),cardiovascular system (8％,4/50),respiratory system (4％,2/50) and facial structures (2％,1/50).Intrauterine death occurred in one case and 49 mothers had a live birth.After birth,14 neonates were normal,five needed further treatment,three cases were complicated by other abnormalities,23 had no dysfunction but need follow-up and four were lost to follow-up.Six of the 20 (30％) fetuses with central nervous system abnormalities and 2/4 fetuses with cardiovascular system abnormalities had an adverse prognosis,while 1/12 and 2/7 fetuses with digestive and urinary system abnormalities had an adverse prognosis.Conclusions The central nervous system and cardiovascular system should be examined in priority during the third trimester ultrasound scan.