Condoms can first prevent sexually transmitted diseases, such as trichomoniasis, which is a common clinical condition. Although it is usually a vaginal infection in women, it can be easily transmitted to the man if a condom is not used. In addition, syphilis, gonorrhea and AIDS can also be transmitted through sexual intercourse, and the use of condoms can prevent the occurrence of these diseases. In addition, with a condom, the male sperm cannot enter the uterine cavity of the woman, so there is no possibility of ectopic pregnancy in this case. In addition, the use of condoms can also treat autoimmune infertility, which is caused by anti-sperm antibodies in the body of women who are exposed to male sperm in the vagina, thus leading to infertility, so women need to use condoms for six months before getting pregnant.