Effect of Phosphodiesterase-5 Inhibitors on the Treatment of Male Infertility: A Systematic Review and Meta-Analysis

Male infertility is a worldwide problem with limitations in the treatment. Phosphodiesterase-5 inhibitors (PDE5is) is the first choice for the treatment of erectile dysfunction, more and more studies show that it has a certain effect on male infertility in recent years. But there was currently no high quality of systematic review to evaluate the effects of PDE5is on semen quality.

We retrieved the electronic databases of MEDLINE, PubMed, Web of Science, EMBASE, etc. Related randomized controlled trials (RCTs) were collected and selected up to May 20, 2020. We have searched literature with terms "male infertility", "phosphodiesterase-5 inhibitors", "PDE5i", "Tadalafil", "Sildenafil", "Vardenafil", "Udenafil", "Avanafil", "semen", and "sperm". Mean value and its standard deviation were used to perform quantitative analysis. All statistical analyses were conducted by RevMan 5.3 and Stata software.

There were a total of 1,121 participants in the nine included studies. There was a statistically significant improvement treated with PDE5is compared with sham therapy, which including sperm concentration (mean difference [MD]=1.96, 95% confidence interval [CI]=1.70-2.21, p<0.001; MD=3.22, 95% CI=1.96-4.48, p<0.001), straight progressive motility (%) Grade A (MD=3.71, 95% CI=2.21-5.20, p<0.001), sperm motility (MD=8.09, 95% CI=7.83-8.36, p<0.001), morphologically normal spermatozoa (%) (MD=0.67, 95% CI=0.20-1.15, p=0.005; MD=1.27, 95% CI=0.02-2.52, p=0.05), sperm abnormalities (%) (MD=-0.64, 95% CI=-0.81--0.47, p<0.001), and progressive motile sperm (MD=5.34, 95% CI=3.87-6.81, p<0.001).

In this meta-analysis of nine RCTs, treatment with PDE5is could improve some indicators of male sperm.