Although most correctable malformations diagnosed in utero are still best managed by appropriate postnatal medical and surgical therapy, in selected cases treatment before birth by fetal surgery may best the beat option. Fetal surgery holds the promise of correcting some fetal problems at an early point in gestation, before fetal injury or death have occurred. Prenatal operative intervention may become the more cost-effective and humane approach to a series of otherwise devastating fetal diseases. Medical fetal therapy is to have drugs and medications during pregnancy duration in order to prevent any fetal defaults. prenatal transplantation has tremendous potential to broaden the current indications for reconstitution therapy and to offer a safe, efficacious, and cost-effective alternative to conven¬tional postnatal BMT for many congenital hematopoietic diseases. Earlier studies have given way to a more realistic approach in gene therapy.