ABSTRACT
This chapter first discusses the prenatal tests, which are used to check that the fetus is normal and healthy. These tests include two categories: screening tests and diagnostic tests. Prenatal screening tests give information about the level of risk of the condition being screened for. Diagnostic tests may then be used to confirm or refute a positive result. The chapter focuses on the most commonly used diagnostic test that is preimplantation genetic diagnosis (PGD). This test allows the analysis of the genotype of an embryo prior to implantation. The chapter summarizes the reasons for referral for PGD. PGD is now available in most European countries. The formation of the European Society for Human Reproduction and Embryology (ESHRE) PGD Consortium may provide some professional self-regulation, and should eventually provide useful statistical data on referrals and outcomes. But in the area of genetic diagnosis quality assurance is essential.
