Future directions in noninvasive Doppler evaluation of the fetal circulation

Doppler gives important new information in the evaluation of the fetal circulation. Doppler can be used for uteroplacental assessment, measurement of blood velocities inside the heart, and diagnosis of the hemodynamic correlates of congenital cardiac defects in utero. Examples of how pulsed, continuous wave, and color Doppler can be used are illustrated. Integration of the cardiac and noncardiac Doppler examinations promises to provide a wealth of information concerning the normal and abnormal developing fetal physiology.