Doppler ultrasonography in obstetrics: from the diagnosis of fetal anemia to the treatment of intrauterine growth-restricted fetuses.

After the adoption of the use of umbilical artery and middle cerebral artery peak systolic velocity in high-risk pregnancies and in pregnancies that are at risk of having an anemic fetus, the main focus of Doppler ultrasonography in obstetrics today is intrauterine growth-restricted fetuses. What is most needed at this time are (1) training of sonographers and sonologists on how to perform a Doppler study, (2) an international classification of intrauterine growth-restricted fetuses, and (3) a study of the natural history of intrauterine growth-restricted fetuses that might contribute to a better understanding of the intrauterine growth-restriction process and to standard treatment of intrauterine growth-restricted fetuses. Future investigations, which would include randomized studies, could be designed from the results of such studies.