Preimplantation genetic diagnosis (PGD)
PGD is a process to evaluate embryos for genetic disorders prior to implantation of the embryos in the uterus. The embryos are typically biopsied, a process in which one or two cells are removed at the eight-cell stage. These cells are then tested for specific genetic defects. The remaining portion of the embryo if free of disease is transferred to the uterus, typically on Day 5.