Abstract
Introduction: We aimed to determine the changes, varieties, and differences of the Doppler index of the umbilical, uterine and fetal middle cerebral artery (MCA) and umbilical vein (UV), ductus venosus (DV), inferior caval vein (ICV) of the normal pregnancies among the 18-37th weeks and the term to determine the normal values of our population.
Materials and Methods: Umblical, uterine, and fetal MCA with UV, DV, and ICV Doppler examinations were performed following the routine obstetric ultrasonographic evaluation once throughout the pregnancy and at the delivery of 163 normal pregnant with no maternal or Fetal complications at 18-24 (66 patient), 25-30 (53 patients) and 31-37 weeks (44 patients). The Systole/Diastole (S/D) rate for the arteries and the ICV, preload index for the DV, and mean velocity for the UV were used as the Doppler indexes. All color Doppler ultrasonographic examinations were performed by only one operator using the Siemens Acuson Antares machine and the CH4-1 MHz convex probe.
Results: During the following weeks of the pregnancy, the S/D Doppler index and DV preload index were found to be decreased. No significant changes were found for the UV mean velocity. Results were statistically evaluated.
Conclusion: As a result, venous structures and arterial parameters should be evaluated during the obstetric color Doppler ultrasonographic examination. The evaluation of these structures can be important for the early diagnosis of the conditions such as intrauterine growth retardation and hypoxia.

Key words: Obstetric doppler, Umblical artery, Uterine artery, Fetal middle cerebral artery, Umblical vein, Ductus venosus, Inferior caval vein