Outcome of varicocelectomy on different degrees of total motile sperm count: A systematic review and meta-analysis

It is crucial to identify the subfertile men with varicocele who will benefit the most from varicocelectomy, and the factors which help in predicting the response to varicocelectomy. We aimed to evaluate the impact of varicocelectomy on total motile sperm count (TMSC) and spontaneous pregnancy (SP) rates. A comprehensive literature search was performed using Medline/PubMed and Google Scholar up to December 26, 2018, with no restriction on language and year of publication. Published articles reporting different degrees of TMSC before and after varicocelectomy in infertile men with varicocele (palpable and/or clinical) were extracted. In addition, SP rates as a function of TMSC after varicocelectomy were reviewed. Potential biases were analyzed to rule out skewing factors. Mean TMSC was graded as: <2 million - profound, 2-5 million - severe, 5-10 million - moderate, and >10 million - mild. Data were analyzed using Stata11. Among the total 96 articles identified through electronic and manual searches of references, nine articles fulfilling the inclusion criteria were included. All degrees of TMSC resulted in a significant postoperative improvement, with only small differences, among the profound [10.20 million (95% confidence interval [CI]: 9.11-11.30, p < 0.0001)], severe [15.77 million (95% CI: 10.65-20.89, p < 0.0001)], and moderate groups [19.18 million (95% CI: 10.40-27.96, p < 0.0001)]. However, the mild group demonstrated a highly significant improvement [49.68 million (95% CI: 38.74-60.62, p < 0.0001)]. After varicocelectomy, the SP rate was highest in the TMSC >20 million group (55.4%), followed by TMSC 5-20 million group (45.4%), and TMSC <5 million group (26.3%). In comparison, the TMSC <1.5 million group demonstrated the lowest SP rate (16.0%). Moderate evidence suggests that varicocelectomy results in a significantly improved TMSC. The improvement in TMSC and SP rates is higher in patients who present a mild or moderate decreased TMSC.Abbreviations: TMSC: total motile sperm count; SP: spontaneous pregnancy; ART: assisted reproductive technology; IVF: in-vitro fertilization; IUI: intrauterine insemination; WMD: weighted mean difference; CI: confidence interval.