The development and evolution of fetal surgery and the recognition of the fetus as a patient came from two sources. First, were those obstetricians and perinatologists who detected life threatening anomalies before birth, and re-described a hidden mortality arising from death in utero. Ultrasonography, color Doppler ultrasound and ultrafast fetal magnetic resonance imaging have since enhanced the accuracy of prenatal evaluation. Second, were those pediatricians responsible for treating newborn infants with extremely serious problems, and that appeared untreatable, although, it was believed that they could have been treated at an earlier stage of development. After the natural history of several correctable lesions had been determined and the selection criteria for intervention developed, fetal surgery emerged as a means of improving the overall morbidity and mortality rates.