The fetal genitourinary tract.

Early recognition of fetal urinary tract anomalies may dramatically influence obstetric or neonatal management. Major fetal urinary abnormalities, including renal agenesis, obstructive lesions, and cystic disease, may be clinically silent but readily identified by sonography. Careful evaluation of the fetal genitourinary tract should therefore be an important component of the routine screening obstetric sonogram. Appreciation of normal sonographic appearances of the fetal genitourinary tract may facilitate early recognition of the abnormal fetus. Accurate prenatal sonographic characterization of a renal abnormality and evaluation of renal function are essential for fetal prognosis and management.