Pre-implantation Genetic Screen / Diagnosis (PGS/ PGD) is a genetic screening diagnostic technology before implantation of the embryo that aims to avoid the transmission of genetic diseases. Technicians perform embryo biopsies on blastocysts to collect some trophoblasts and use gene-chips or next-generation DNA sequencing for genetic analysis. Due to the high risk of damaging oocytes or early embryo, at HuaYu Fertility, we prefer the blastocysts biopsy instead of collecting polar bodies or one of the cells in 8-cells to morula stage.  This technology allows embryos to be tested before implantation to remove embryos with genetic diseases or chromosomal abnormalities, in order to reduce uncertainty during pregnancy, increase live birth rates, and avoid the physical and mental stress caused by abortion.