There are three major tests that must be done before a man can get pregnant, including chromosome test, semen analysis test and scrotal ultrasound test. The main purpose of these three tests is as follows: 1) chromosome test, mainly to determine whether there is a problem with the genes of men. If there are problems with the genes, it may lead to the inability to have children; 2, semen analysis test is mainly to determine the quality of semen, which can also determine the fertility of men, is a more important indicator; 3, scrotal ultrasound examination, mainly to determine the size, texture, whether the testicles accounted for, etc., can also initially determine the fertility of men.