The Impact of Bacteriospermia on Semen Parameters: A Meta-Analysis

Objective: To evaluate the impact of bacteriospermia on semen parameters. Materials and methods: We used the Medline (1966-2017), Scopus (2004-2017), Clinicaltrials.gov (2008-2017), EMBASE, (1980-2017), LILACS (1985-2017) and Cochrane Central Register of Controlled Trials CENTRAL (1999-2017) databases in our primary search along with the reference lists of electronically retrieved full-text papers. Meta-analysis was performed with the RevMan 5.3 software. Results: Eighteen studies were finally included. Men were stratified in two groups, healthy controls (5,797 men) and those suffering from bacteriospermia (3,986 men). Total sperm volume was not affected by the presence of bacteriospermia when all pathogens were analyzed together (MD 0.02 95%CI -0.13,0.17). Both sperm concentration (MD -27.06, 95% CI -36.03, -18.08) and total sperm count (MD -15.12, 95% CI -21.08, -9.16) were significantly affected by bacteriospermia. Decreased rates of normal sperm morphology were also found (MD -5.43%, 95% CI -6.42, -4.44). The percentage of alive sperm was significantly affected by bacteriospermia (MD -4.39 %, 95% CI -8.25, -0.53). Total motility was also affected by bacteriospermia (MD -3.64, 95% CI -6.45, -0.84). In addition to this, progressive motility was significantly affected (MD -12.81, 95% CI -18.09, -7.53). Last but not least, pH was importantly affected (MD 0.03, 95% Cl 0.01, 0.04). Conclusion: Bacteriospermia significantly affects semen parameters and should be taken in mind even when asymptomatic. Further studies should evaluate the impact of antibiotic treatment on semen parameters and provide evidence on fertility outcome.