Among the causes of male infertility, sexually transmitted diseases, called venereal diseases, are among the causes of the reduction in the quantity and quality of sperm that can induce infertility – explains Dr. Luciano Negri, assistant andrologist at the Fertility Center in Humanitas. Sexually transmitted infections have increased in recent years, increasing by 30% in the sexually active population. Venereal diseases responsible for the increased risk of infertility, shared with women to a lesser extent, include chlamydia trachomatis, urealyticum ureaplasm, gonorrhea, syphilis and papillomavirus infections. These are often asymptomatic infections, which spread from the urethra to the prostate and up to the epididymis in men. The epididymis is a duct from which semen is spilled and damaged to the point of obstruction. In general, only when the infection manifests itself in symptoms such as fever, severe urinary disorders, urethral secretion or the appearance of warts, the man is convinced to see a doctor and therefore treated effectively. Therefore, the risk of male infertility that derives from sexually transmitted diseases can be reduced by avoiding risky sex and using condoms, even if there is no absolute guarantee of avoiding infection. If you suspect that you have been having unsafe sex, you should consult your doctor for research into HIV, hepatitis C and syphilis. In addition, you should identify the classic bacteria of venereal infections with a urethral swab, so that your sexual partner is also protected from the risk of infection.