Add to ORKGSince 1998, the Japan Society of Obstetrics and Gynecology has placed severe restraints on preimplantation genetic diagnosis of embryos (PGD). However, finally (in 2006), the Society approved the clinical application of PGD to habitual abortion due to structural chromosomal abnormalities as well as to serious genetic diseases such as Duchenne muscular dystrophy (DMD) and myotonic dystrophy. But, it has not yet approved the clinical application of PGD to habitual abortion due to numerical chromosomal abnormalities, although the number of these patients is much greater than the number of patients suffering from habitual abortion due to structural chromosomal abnormalities.\The reason why the Society still places severe restraints on PGD is be...