TABLE 2.

Summary of the studies reporting the reproductive consequence of varicocele.

Subjects	Reproductive consequences	References
Human	Poorer semen quality; higher serum levels of FSH; lower inhibin B; higher levels of LH	Damsgaard et al., 2016
Human	Sperm DNA damage	Ni et al., 2016
Human	Smaller testis; higher frequency of abnormal epididymis	Zhang et al., 2017
Human	A reduction in the concentration/mL and the total sperm number	Pallotti et al., 2018
Human	Lower sperm production and motility; increased percentage of abnormal sperm morphology	Oliva and Multigner, 2018
Rat	lower sperm count and survival rate; disordered seminiferous epithelium	Zhao et al., 2019
Human	Lower sperm parameters, sperm and leukocyte telomere length; higher DNA fragmentation, protamine deficiency, and lipid peroxidation	Tahamtan et al., 2019
Human	Higher sperm DNA fragmentation index	Nguyen et al., 2019
Human	Lower total and total motile sperm counts; slightly higher testosterone levels	Redmon et al., 2019
Human	Non-obstructive azoospermia	Kavoussi et al., 2019
Human	Decreased sperm quality	Santana et al., 2020
Human	Higher DNA fragmentation index; decreased all semen characteristics; an abnormality of at least one of the spermatic parameters	Jellad et al., 2021
Human	Higher sperm DNA fragmentation and apoptosis rate	Ammar et al., 2021
Human	Reduced semen parameters; increased sperm DNA fragmentation	Finelli et al., 2021
Human	Lower sperm concentration, motility and total sperm count;higher serum FSH levels, and higher seminal oxidation-reduction potential and sperm DNA fragmentation index	Tanaka et al., 2020