A Preliminary Study Of Fetal Ductus Venosus Flow Waveforms At 10-20 Week Gestation

Objective: to establish reference values range of RI,S/A and PI for ductusvenosus flow velocities waveforms at 10-20 weeks of gestation and explorethe measurement of obtaining ductus venosus flow velocities waveformstransabominally at this stage .discuss the occurrenc rate of reversed flow duringatrial contraction (RA) in fetal of 10-14 weeks .Methods : Ductus venosus flow velocities waveforms was obtainedrandomly from 100 normal singleton pregnancies at 10-20 weeks of gestationthat come to peking union hospital for a regular exam.fetuses withchromatosome disformation,severity heart disformation and growth-retardedfetus was exclude . Reference values of RI,S/A and PI was constructed bymeans of regression model .Result: The value for RI,S/A and PI decrease with increaseing gestationalage.The 95% reference values for RI,S/A and PI are (0.34,0.90), ( 1.23,6.65)和 (0.21,1.32) respectively. zero or reversed A(RA) wave was not discoveredin this study.Conclusion: assessment of ductus venosus blood flow velocity waveformsduring first and second trimester is feasible by means of color dopplerultrasound transfabominally. reference values range of RI , S/A and PIestablished in this study may be utilized in studies dealing with the role ofductus venosus blood flow in chromosomal abnormal fetuses ,fetuses withcongenital heart disease or growth-retarded fetuses.