[Is bacteriological screening of semen samples before in vitro fertilization treatment justified?]

The number of couples seeking assisted reproductive technologies is increasing worldwide. The question of whether routine bacteriological screening of semen is necessary during the investigation and treatment of infertility is controversial. The semen sample often contains bacteria even if the hygiene rules for collection are followed. There is a growing number of studies dealing with the importance of the semen microbiome. Bacteriospermia can result not only from infection but also from contamination or colonization. Symptomatic infections or sexually transmitted diseases should be treated, but the relevance of asymptomatic positive cultures is controversial. Several studies have suggested that urinary tract infections may play a role in male infertility and that the quality of semen may be impaired by elevated bacterial or white blood cell counts. However, there are conflicting results on the effect of the treatment of bacteriospermia and leukocytospermia on sperm quality. Semen contaminated with microbes may also infect the embryos, thus compromising the success of treatment. In contrast, most studies have found no significant difference in the effectiveness of in vitro fertilization treatment in the presence or absence of bacteriospermia. This can be explained by the sperm preparation techniques, the antibiotic content of the culture media and the use of the intracytoplasmatic sperm injection technique. Thus, the need for routine semen culture before in vitro fertilization treatment and the management of asymptomatic bacteriospermia is questionable. Orv Hetil. 2023; 164(17): 660-666.