People with genetic disorders or their parents should always do genetic counseling before deciding to have the next generation. It is an absolute mistake to come back after pregnancy and ask if the child is at risk, when there is usually no time for prenatal diagnosis and we cannot help you. Prenatal diagnosis is required for hereditary diseases, and stopping the inheritance of the disease within the family is not only the responsibility of the nation, but also a responsibility that should be assumed by the family members. Before having prenatal diagnosis both spouses should fully discuss and prepare themselves psychologically. The steps to perform prenatal diagnosis are: 1. Specific diagnosis of genetic diseases and mutated genes to clarify the mode of inheritance. Generally the examination from a previous onset patient can be determined. 2, clarify which diseases can be genetic examination, generally nuclear gene mutation patients with sex-linked inheritance and dominant mode of inheritance, need to do prenatal genetic examination, recessive inheritance is generally not transmitted to the children’s generation, but to the generation of grandchildren, grandchildren need genetic examination. Mitochondrial disease caused by mitochondrial gene mutation, generally through genetic examination can not determine whether the next generation has mitochondrial disease. 3. It is necessary to sign an agreement with the hospital to be able to perform prenatal genetic diagnosis tests. We will work with the neurologist and obstetrician-gynecologist of the hospital where we will be seen and the technician who will perform the genetic test to determine the timing of the pregnancy and the time of the prenatal test. Generally, genetic tests are performed at 12 weeks of pregnancy for chorionic villus, 16 weeks for amniotic fluid, and 20 weeks for umbilical cord blood. 4. If both parents have the disease-causing gene, IVF can also be performed by combining someone else’s sperm or egg with their own egg or sperm to form an embryo, which is then implanted in the uterus. 5. The parents have no disease-causing genes, and it is determined that the child has a de novo mutation of its own, without the need for prenatal genetic testing.