Due to the technical requirements of prenatal diagnosis of genetic diseases or genetic metabolic diseases, it should be performed only on the basis of a clear genetic diagnosis and enzymatic diagnosis of the person with a preexisting condition. On the contrary, if you do not come to our department for a preconception to have a confirmatory genetic or enzymatic test, you may not be able to perform prenatal diagnosis if you come directly to pregnancy. If the family line of the preexisting patient is no longer present and genetic diagnosis of the patient is not possible, it is also possible to start with the genes of the parents, but all tests need to be done before conception! Prenatal diagnosis is usually performed by taking amniotic fluid from the mother at the 17th week of pregnancy. We also provide chromosome testing for each pregnant woman.