Condoms can prevent certain diseases in clinical use, but only relatively and not to the extent of absolute prevention. For example, if there is pubic lice, the contact of pubic hair can lead to infection at all, although the condom is used. In the case of vulvovaginal pseudomonal yeast disease, although the glans and penis are not clinically contaminated, the part of the pubic hair may also be infected with pathogenic bacteria, which can also cause symptoms of infection in the male external genitalia. In clinical terms condoms are only relatively able to block disease and reduce the occurrence of infectious diseases, but not absolutely. Do not have a history of high-risk sex in the clinic, once you have a history of high-risk sex, it is possible to transmit some STDs or other diseases. In addition, if you use condoms for contraception between couples, it is also clinically recommended to use condoms throughout sexual intercourse to achieve better contraceptive purposes.