Although there is extensive literature regarding ultrasonic biometric evaluation of the fetus, our goal is to establish nomograms for the visualization of fetal organs, as they have not previously been reported. Data from the first complete ultrasound examination of 2,389 consecutive gravidas at greater than or equal to 14 weeks gestation were analyzed. The examinations were performed by three registered sonographers during a 20-month period. Fetal cerebral ventricles, heart, stomach, kidneys, intestines, bladder, diaphragm, spinal column, extremities, and umbilical cord were examined routinely and classified as normal, abnormal, or suboptimally visualized. Ultrasound visualization of these organs varied with gestational age (P less than 0.0001) and patterns of visualization varied markedly by organ. These nomograms could be useful in the timing of ultrasound examinations, the timing and method of delivery, detection of anomalies amenable to in utero therapy, parental counseling, quality assurance programs, and medicolegal liability defense.