Abstract
The assessment of fetal well-being by venous Doppler velocimetry, especially in cases of intrauterine growth restriction, has been growing in importance as a number of researchers have been improving their studies<citeref rid="b1"><emph>1</emph></citeref> - <citeref rid="b2"></citeref><citeref rid="b3"></citeref><citeref rid="b4"></citeref><citeref rid="b5"><emph>5</emph></citeref> as well as a consequence of better technologies in ultrasound equipment. Since different authors have studied the fetal blood circulation with color Doppler, initially focusing their attention on the arterial system<citeref rid="b6"><emph>6</emph></citeref> - <citeref rid="b7"></citeref><citeref rid="b8"></citeref><citeref rid="b9"></citeref><citeref rid="b10"></citeref><citeref rid="b11"></citeref><citeref rid="b12"><emph>12</emph></citeref>, many questions and doubts have remained without a reasonable answer, especially concerning the optimal time at which to deliver these fetuses. Among these authors, some have expressed the opinion that all biophysical methods, including the cardiotocogram, should be used before the decision of fetus delivery should be made<citeref rid="b13"><emph>13</emph></citeref>,<citeref rid="b14"><emph>14</emph></citeref>. It is possible, nowadays, to study several venous vessels, such as the ductus venosus, inferior vena cava, umbilical vein, portal vein, hepatic veins<citeref rid="b15"><emph>15</emph></citeref>, and, more recently<citeref rid="b1"><emph>1</emph></citeref>,<citeref rid="b2"><emph>2</emph></citeref>, the cerebral transverse sinus. The purpose of this review is to describe the fetal circulation, the technique and rationale behind measuring venous Dopplers and to assess the clinical applications of venous Doppler velocimetry.