Preimplantation diagnosis (PID) offers couples at high risk of having
offspring affected with a genetic disorder the possibility of an early
prenatal diagnosis. For many couples this approach will give the oppo
rtunity to avoid a selective termination of affected pregnancies. Subs
tantial advances were made in PID since the report, in 1990, of the fi
rst birth obtained after PID. Yet, many technical hazards have to be s
olved for PID to become a standard clinical tool. The very close corre
lation existing between the forthcoming developments in the fields of
PID and human genome mapping will improve the reliability and efficien
cy of genetic diagnosis. In the near future, the procedure may also be
come easier and safer. As a consequence, the indications for PID could
be extended to other genetic defects, such as multifactorial diseases
. They could also be extended to cases with no medical background, suc
h as social gender selection or behavioural traits. in this perspectiv
e, it is now time for both the medical and scientific communities to i
dentify the ethical issues related to these potential new indications.