Effect of Bariatric Surgery on Semen Parameters: A Systematic Review and Meta-Analysis.

BACKGROUND The present systematic review and meta-analysis was performed to explore the possible effect of bariatric surgery on semen parameters. MATERIAL AND METHODS Studies on the effect of bariatric surgeries on semen parameters were collected by searching Cochrane Library, PUBMED, EMBASE, MEDLINE, and CNKI databases. We extracted information on essential data and outcome measures, including study design, bariatric surgery, and semen parameters at baseline and after the surgery from the included studies, and STATA 12.0 software was applied to conduct the meta-analysis. Predefined subgroup analyses were also conducted by study design and bariatric surgical procedures. The standard mean difference (SMD) was calculated to estimate the effect on semen parameters. RESULTS After the literature search, 6 articles that fulfilled the inclusion criteria were included in the present meta-analysis. The results revealed that patients who had undergone gastric bypass surgery had an increase in semen volume (SMD (95%CI)=0.583 (0.121-1.045), p=0.013). However, the seminal concentration (overall, SMD (95%CI)=-0.123 (-0.418-0.173), p=0.416) and the semen progressive motility (overall SMD (95%CI)=0.148 (-0.148-0.444), p=0.328) remained unchanged after the bariatric surgery. Nevertheless, semen normal morphology experienced an increase in the subgroup of prospective design and sleeve gastrectomy (prospective study, SMD (95%CI)= 0.385 (0.074-0.697), p=0.015, sleeve gastrectomy, SMD (95%CI)=0.880 (0.465-1.296), p=0.000; overall, SMD (95%CI)=0.372 (0.068-0.677), p=0.017). CONCLUSIONS In conclusion, based on the limitations of the present meta-analysis, definite conclusions cannot be reached regarding the possible effect of bariatric surgery on semen parameters.