Since its inception in 1978, in vitro fertilization (IVF) has provided a pathway to parenthood for millions, with over 8 ...

This process, known as blastocyst complementation, involves injecting rat stem cells into mouse blastocysts—early-stage embryos lacking the ability to develop a pancreas due to genetic mutations.

However, to create ES cell lines, it is necessary to destroy preimplantation embryos at the blastocyst stage of 100–200 cells. Many people believe that life begins at conception and that ...