Some couples with a high risk of transmitting an inherited condition, cystic fibrosis, Beta-thalassemia, sickle cell disease and many others, opt for ART with the objective of preventing the transmission of the disorder. In these cases, Pre-implantation Genetic Diagnosis (PGD) is used to select embryos for implantation that do not carry the condition. 
An error in the process of PGD might lead to the birth of a child with the particular condition. However, the test has an expected error rate so it could be argued that this type of outcome should not be considered as an issue for vigilance reporting. Monitoring cases of PGD error, which result in the birth of children with the condition that the treatment aimed to avoid, would allow trends to be followed and facilitate regulatory action where PGD error is more frequent than normal.
Where an error in PGD results in the birth of a child with the condition that should have been avoided, this should be considered as a reportable adverse occurrence with harm to a fetus/offspring so that the cause can be investigated and the learning points shared.forming the clinic could protect other