Recent scenario of obesity and male fertility.

The aim of this review was to provide current scenario linking obesity and male fertility. Obesity has been linked to male fertility because of lifestyle changes, internal hormonal environment alterations, and sperm genetic factors. A few studies assessing the impact of obesity on sperm genetic factor have been published, but they did not lead to a strong consensus. Our objective was to explore further the relationship between sperm genetic factor and obesity. There are emerging facts that obesity negatively affects male reproductive potential not only by reducing sperm quality, but in particular it alters the physical and molecular structure of germ cells in the testes and ultimately affects the maturity and function of sperm cells. Inhibition of microRNA in the male pronucleus of fertilized zygotes produces offspring of phenotypes of variable severity depending on miRNAs ratios. Hence, these RNAs have a role in the oocyte development during fertilization and in embryo development, fetal survival, and offspring phenotype. It has been reported that the miRNA profile is altered in spermatozoa of obese males, however, the impact of these changes in fertilization and embryo health remains as yet not known.