1. Having not had a premarital examination;
2. Both or one of the couple has genetic history, family genetic history, chronic disease and infectious disease;
3. Couples with infertility, recurrent spontaneous abortion and stillbirth history;
4. The age of the woman is ≥ 30 years old;
5. Have a history of adverse labor, such as habitual abortion, stillbirth, stillbirth, mental retardation;
6. Couples who have not been vaccinated against hepatitis B;
7. The couple are exposed to adverse factors in their work and life, such as exposure to radioactive substances, chemical pesticides, harmful environment, etc;
8. Have bad living habits, such as long-term smoking, drinking, drug addiction, partial eating, etc;
9. People who keep pets.