To elucidate the association between asymptomatic infections caused by Mycoplasma hominis and male infertility and to evaluate the role of antibiotic therapy in the treatment of this failure.

A total of 165 infertile men having abnormal semen parameters (study group) as well as 165 healthy fertile men (control group) were included in this study. Semen samples were taken from all participants and, after analyzing for semen parameters, real-time polymerase chain reaction, microbial culture, and reactive oxygen species (ROS) as well as total antioxidant capacity (TAC) assays were performed. Infected individuals of the study group were treated with antibiotic. One month after the treatment completion, second semen samples were taken and all the tests mentioned were performed. The data were analyzed using SPSS statistical software, version 22.0.

The frequency of M. hominis was significantly higher in the infertile men compared with the fertile ones (14.5% vs 3.6%, P = .001). The mean cycle threshold (C_t) value was lower in infected infertile men than in infected fertile men (P < .001). All semen parameters, except volume, pH, and viscosity, were improved (P < .05), most of which reached their normal range; leukocytes in seminal fluid were eliminated (P = .04); the level of TAC elevated (P < .001); and the ROS level as well as the ROS-to-TAC ratio reduced after antibiotic treatment (P = .02). Moreover, wives of 14 infected infertile men (58.3%) became pregnant 4 months after the treatment completion.

Our data suggest that asymptomatic infection caused by M. hominis is correlated with male infertility and antibiotic therapy can improve the semen quality and fairly treat the male infertility.