Future directions

With the continued explosion of genetic technology, the number of disorders amenable to screening is expanding geometrically. Historically, most genet ic screening has been in the newborn period. Much more can be done for the fetus if genetic screening and diagnosis are accomplished early in the preg nancy rather than after birth. The principal requirements to make neonatal screening disorders possible in the first trimester center around those tes ts that can be one on a molecular basis, and the development of fetal cell isolation from the maternal circulation. Over the course of the next decade , it is likely that many of the tests currently performed in the newborn pe riod will be accomplished in the early or mid-gestational period.