Reference Centile Chart for Umbilical Vein Maximum Flow Velocity in Thai Fetuses Throughout Pregnancy

Objective:  To create a reference centile chart for umbilical vein maximum flow velocity (UVVmax) in Thai fetuses. Methods:  The study was a prospective, cross-sectional study, carry out at the Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Faculty of Medicine Siriraj Hospital, Mahidol University. A total of 780 pregnant women between 13 and 40 weeks' gestation, who attended the antenatal clinic of Siriraj Hospital, Mahidol University, Bangkok, were recruited. Each fetus was measured only once for the purpose of this study. The mean and standard deviation (SD) were estimated at each week of gestation using linear regression modeling. A total of 752 fetuses were measured for UVVmax. Results:  Linear regression models were fitted to estimate the mean 95% confidence interval for UVVmax at each gestational age. The centile chart was also presented.  Conclusion:  The reference centile chart for fetal UVVmax of Thai fetuses was created.