The reversibility of sperm quality after discontinuing nandrolone decanoate in adult male rats.

AIM To investigate the reversibility of the effect of nandrolone decanoate (ND) on sperm parameters after discontinuing the drug. METHODS Three groups of rats received peanut oil (control), low and high doses of ND for 14 weeks, respectively. Each group was divided into subgroups A and B, in which rats were killed 14 and 28 weeks after initiating the injection, respectively. RESULTS Sperm count and motile sperm fraction were decreased in the subgroups A and B that received low and high doses of ND in comparison with the controls A and B, respectively. The sperm count and motile sperm fraction increased in the subgroups B that received low and high doses of ND in comparison with their corresponding subgroups A. The number of normal morphology sperm was decreased significantly in subgroups A receiving low and high doses of ND in comparison with the control subgroup A. However, this parameter was not decreased in subgroups B receiving low and high doses in comparison with the control subgroup B. The normal sperm morphology did not show any significant differences in the subgroups B in comparison with their corresponding subgroups A. CONCLUSION The 14-week injection of low and high doses of ND decreases sperm quality and quantity in rats. These parameters were improved after discontinuing ND, but not recovered completely even when they are left untreated for 14 weeks.