Objective      To investigate the clinical characteristics of chromosomal karyotypes in fetal umbilical venous blood during prenatal diagnosis.       Methods      The chromosomal karyotypes in fetal umbilical venous blood of 438 patients who were admitted in our hospital from January 2006 to December 2011 and underwent cordocentesis were analyzed. The chromosomal karyotypes were compared in different organ and system abnormalities indicated by systematic ultrasonography.       Results      In the patients with systematic ultrasonography-indicated fetal abnormalities and elder pregnant patients

the rates of abnormal chromosomal karyotypes were 18.2% and 12.9%

the rates of trisomy (21/18/13) were 10.7% and 8.1%

and the rates of abnormal chromosomal karyotypes with trisomy (21/18/13) were 58.9% and 62.5%. In the patients with fetal abnormalities of digestive system and skeletal system

the rates of trisomy 21 were 33.3% and 35.0%

and the rates of abnormal chromosomal karyotypes with trisomy 21 were 75.0% and 87.5%. As for the patients with fetal abnormalities of nervous system and cardiovascular system

the rates of trisomy 18 were 21.4% and 9.7%

and the rates of abnormal chromosomal karyotypes with trisomy 18 were 69.2% and 50.0%.       Conclusion      (1) The patients with systematic ultrasonography-indicated fetal abnormalities and the elder pregnant women have a relatively high incidence of abnormal chromosomal karyotypes

and amniocentesis or cordocentesis should be performed in prenatal diagnosis. (2) The fetal abnormalities in digestive system

skeletal system

nervous system and cardiovascular system are closely related to chromosomal karyotype abnormalities. Abnormalities of digestive or skeletal system are more possibly found in fetus with trisomy 21

while those of nervous or cardiovascular system are more possibly found in fetus with trisomy 18.