Premarital examination is a routine physical and reproductive examination of both men and women before marriage in order to detect diseases. The content of premarital examination includes two major parts: asking medical history and physical examination. A, ask items: 1, whether the two sides have common blood relations. 2, the parties’ current and past medical history and medication history. The history of both parties’ personal life, recent work and living conditions, smoking and drinking habits, etc. The female partner’s menstrual history and the male partner’s seminal emission. In case of remarriage, ask about the history of previous childbirth. 4. Both parties’ families have any congenital severe disabilities, with emphasis on asking about the history of genetic-related diseases. 2. Physical examination, including internal examination, genital examination and laboratory examination. 1, internal examination, that is, the whole body examination, such as heart, liver, spleen, lungs, kidneys, as well as blood sugar, blood pressure and heart rate. 2.Genital examination is to detect genital diseases that affect marriage and fertility. Abnormalities of the reproductive system. Such diseases directly affect fertility, some of which can be diagnosed by male and gynecologists through the naked eye, some need to use ultrasound examination. In the case of females, the hymenal atresia, vaginal atresia, uterine dysplasia, uterine fibroids, etc.; in the case of male genitalia, the presence of prepuce, penile nodules, short penis, hypospadias, cryptorchidism, small testicles and syringomyelia, etc. should be noted. 3, laboratory tests, in addition to routine blood, urine, chest X-ray, liver function and blood type, women for vaginal secretions to find trichomonas, mycobacteria, gonorrhea smear test if necessary; men for semen routine laboratory tests. Legal infectious diseases. These include AIDS, gonorrhea, syphilis, hepatitis B, etc. These diseases can be detected by blood sampling or smear. 4. More serious psychiatric diseases, such as severe mania and schizophrenia, etc. Such diseases need to be diagnosed by psychiatrists. Congenital genetic disorders. Such as albinism, primary epilepsy, chondrodysplasia, ankylosing muscular dystrophy, hereditary retinitis pigmentosa, etc. The exclusion of hereditary disorders requires chromosome testing.