Prenatal screening is done by either amniocentesis or chorionic villi sampling during fetal gestation. If a couple believes they are at risk of having a child with a genetic disease, there are a certain number of options. They can choose not to reproduce at all, accept the risk and reproduce anyway, use artificial reproduction technologies, or use prenatal diagnosis to search for the known disorders and possibly abort an affected child. Theoretically, the technology is almost available to alter the genetic code so that the child will be healthy no matter what.