Fetal diagnosis and fetal surgery

Accurate fetal diagnosis became possible by the steadily increasingly complex techniques of amniocentesis, ultrasound, and ultrasound-guided fetal blood sampling and chorion villous sampling. A high degree of diagnostic accuracy for a wide variety of structural and metabolic anomalies is required. The field of fetal diagnosis has been extended to the point that a journal dedicated to this subject alone is a viable proposition. It is becoming apparent, however, that lesions that were well known and well understood when recognized in neonatal life appear in general to have a worse prognosis if the lesion is diagnosed in utero. Fetal surgery began with attempts to perform in utero transfusions for babies with erythroblastosis fetalis. For a while, there was competition between open surgical procedures and the percutaneous placement of blood through catheters introduced into the fetal peritoneal cavity from outside the mother's abdomen. For fetal transfusion, closed techniques proved far safer and just as efficacious. There has been a worldwide interest in shunting of hydrocephalus and obstructive uropathy. The results of shunting hydrocephalus have been disappointing, with most of the patients surviving, but most of the survivors being severely handicapped. The results of shunting obstructive uropathy were that only about 50 per cent of the babies survived, but it appeared that those that did survive did well. Other lesions that have been shunted have been hydrothoraces or fetal ascites. A limited number of open procedures have been carried out in the last few years in San Francisco, and it may well be that diaphragmatic hernia (in appropriately selected patients) will be a lesion that can be corrected by in utero surgery. The future of this field is exciting, but before this form of treatment becomes routine, the ethical implications of the possibility of fetal surgery must be defined much more clearly than is currently the case.