Editing Intracytoplasmic sperm injection (section)

=== Preimplantation genetic diagnosis (PGD) ===
PGD is a process in which one or two cells from an embryo on Day 3 or Day 5 are extracted and the cells genetically analyzed. Couples who are at a high risk of having abnormal number of [[chromosome]]s or who have an history of single gene defects or chromosome defects are ideal candidates for this procedure. It is used to diagnose a large number of genetic defects at present.{{citation needed|date=July 2018}}