Spermatozoa and Chronic Treatment with Finasteride: A TEM and FISH Study

This study investigated the effects of chronic treatment with finasteride on sperm quality in three men. The study found that the drug caused a total absence of sperm in one patient, and severely reduced rapid and slow progressive motility in the other two patients. Sperm ultrastructure analysis showed high necrosis, and FISH sperm analysis showed elevated frequencies of aneuploidy. After cessation of finasteride, one patient showed recovery of spermatogenesis, but sperm pathologies were still higher than controls. The study suggests that chronic treatment with finasteride may have negative effects on male fertility.