Yury Verlinskyand Anver Kuliev Reproductive Genetics Institute, Illinois Masonic Medical Center, 836 W. Wellington chicago, IL 60657 Although introduction of a first trimester prenatal diagnosis by chorionic viIIus sampling (CVS) has considerably improved the possibility for prevention of genetic diseases, it requires a selective abortion in case of an affected fetus. Following the direction of an earlier prenatal diagnosis and to avoid the need for abortion, preimplantation genetic diagnosis has been initiated based on polar body removal and pre-embryo biopsy. The First International...