The optimal age for human reproduction is between 20-35 years old, which is the period of mature sexual development and active sexual function, and STDs are also most likely to occur at this age, and STDs can seriously affect the fertility of patients. Currently, the highest incidence in China is non-gonococcal urethritis, chlamydia, mycoplasma can invade the uterus and fallopian tubes, causing pelvic inflammatory disease, which ultimately leads to fallopian tube scarring obstruction, but also can invade the male reproductive organs, such as epididymis, vas deferens, these reproductive organs are infected, due to the inflammatory reaction can make the official wall blockage, sperm or egg can not pass, and cause permanent sterility. Another STD that affects fertility is syphilis. The infertility rate of women with active syphilis is as high as 23%-40%, which is twice as high as that of normal people. After 4 months of pregnancy, syphilis spirochetes can infect the fetus through the placenta, and at the same time, multiple small arteritis occurs in the placenta, and the fetus cannot obtain nutrition, resulting in premature labor, miscarriage and stillbirth. Even if the baby is delivered at full term, about 57% of the babies are stillborn, and the congenital syphilis children who survive are also very high in mortality rate. The mortality rate is also very high.