Establishment of reference ranges for ductus venosus waveform indices in the Japanese population.
OBJECTIVE
To establish reference ranges for ductus venosus waveform indices in the Japanese population.


METHODS
In this retrospective cross-sectional study, 791 singleton fetuses of healthy Japanese couples were examined from January 2004 to January 2008. Reference ranges for ductus venosus waveform indices were constructed from cross-sectional data obtained at between 18 and 41 weeks of gestation.


RESULTS
With a success rate of 84%, a total of 667 measurements in 791 women were eligible for analysis. The median pulsatility index (PI) of fetal ductus venosus decreased from 0.54 at 18 weeks of gestation to 0.30 at 41 weeks of gestation. The median end-diastolic velocity/peak systolic velocity (a/S) of the ductus venosus increased from 0.56 at 18 weeks of gestation to 0.76 at 41 weeks of gestation.


CONCLUSIONS
In this study, we established reference ranges for the PI and a/S of the ductus venosus in the Japanese population, which differed slightly from other published reference data. The results will be useful for further studies to determine the validity of the clinical importance of the ductus venosus for at-risk fetuses.
Department of Obstetrics and Gynecology, Niigata University School of Medicine, 1-757 Asahimachi, Chuo, Niigata, 951-8510, Japan. yatyayaya@yahoo.co.jp.
Yasuhiro
Y
Takahashi
Department of Obstetrics and Gynecology, Niigata University School of Medicine, 1-757 Asahimachi, Chuo, Niigata, 951-8510, Japan.
Keisuke
K
Ishii
Department of Obstetrics and Gynecology, Nagaoka Chuo General Hospital, 2041 Kasawaki, Nagaoka, Niigata, 940-8653, Japan.
Keisuke
K
Honda
Department of Obstetrics and Gynecology, Niigata University School of Medicine, 1-757 Asahimachi, Chuo, Niigata, 951-8510, Japan.
Akira
A
Kikuchi
Department of Obstetrics and Gynecology, Niigata University School of Medicine, 1-757 Asahimachi, Chuo, Niigata, 951-8510, Japan.
Koichi
K
Takakuwa
Department of Obstetrics and Gynecology, Niigata University School of Medicine, 1-757 Asahimachi, Chuo, Niigata, 951-8510, Japan.
Kenichi
K
Tanaka
Doppler velocimetry; Ductus venosus; Fetus; Reference range; Ultrasound