Fetal drug therapy: an overview of selected conditions.

Fetal drug therapy may be defined as the administration of any drug for the primary or sole purpose of treating a fetal disorder or in the hope of improving the capacity for later intrauterine or postnatal adaptation. In several intrauterine conditions, the drug exposure has been directed at the fetus rather than the mother. Progress in clinical investigation has been slowed by often unfounded fears of malformations and potential litigation. Since 1975, federal regulations have required that the fetus be protected and subjected to no more than minimal additional risk. Although no large-scale trials have been reported, drug administration has been proven to aid the fetus in many circumstances. Such treatment has been administered primarily during the second or third trimester and is generally short-term, preventive, and without apparent risk to the consenting mother. The published reports have made obstetricians aware of both the limits of our knowledge in this area and new applications for innovative fetal monitoring by the latest technology. Whether such therapy has a role in the care of the unborn infant will depend on accumulation of a larger body of information and the continued cooperation of basic scientists and clinical investigators.