The approach to developing a differential diagnosis to an abnormal gastrointestinal ultrasound finding should include consideration of the lesion's location, size, shape, and echogenicity; fetal gender; relationship to and understanding of adjacent structures; and the presence of associated anomalies. Once a differential diagnosis has been established, ancillary testing, such as amniocentesis, maternal serology, or fetal echocardiography should be undertaken to refine further the diagnosis. A multidisciplinary team approach should be taken in the prenatal management of a suspected fetal anomaly. This may include collaboration with specialists in the fields of perinatology, prenatal ultrasound, genetic counseling, neonatology, pediatric surgery, and patient support groups.