It is certain that wearing condoms correctly not only can prevent pregnancy, but also can prevent STDs to a certain extent, although not 100%, but can significantly reduce the probability of contracting STDs. According to the U.S. Department of Health and Human Services bulletin, people who consistently use condoms have an 85 percent lower risk of HIV infection than those who never use condoms. Studies have also shown that in areas with a high prevalence of herpes simplex virus type 2, if only 1/4 of the population used condoms during sex, women’s risk of infection would be reduced by 92%! There are no absolutely safe sexual partners, only relatively safe sexual practices. As the main way of STD transmission, the process of sexual intercourse can spread the secretions carrying pathogenic microorganisms to the other party, infecting them with STDs, and the principle of condom prevention is to act as a physical barrier to block out all pathogens and say “No” to secretions with pathogens. The physical barrier, why can not be 100% defense against STDs? Condoms are like a rubber net, natural latex condoms have many small holes more than 120 nanometers in diameter, can only be similar to the diameter of human sperm size particles (diameter of about 3000 nanometers) effective barrier, and for the diameter of the particles equal to or less than 120 nanometers and can not be completely blocked, HIV, hepatitis B virus, human papillomavirus (HPV) and other viruses are far smaller than sperm particles, completely have It is possible to penetrate traditional natural latex condoms. It is possible to penetrate traditional natural latex condoms, so there is still a risk of disease. 3, other factors: condom isolation area is limited, can not cover all the skin in sexual contact, such as the perineum and other parts of the scrotum is still exposed; when taking off, there is also the risk of vaginal secretions outside the condom, as well as during sexual intercourse condom slipped, broken, may lead to increased risk of disease. It is important to use condoms properly, even though they are not 100% protected against STDs! If a partner is diagnosed with an STD, the most effective means of fighting it is to avoid sexual activity and to treat it in an aggressive way, curing it at the source.