TLDR Finasteride may worsen infertility in men with existing issues, but stopping it can improve sperm health.
This article discusses three cases of male infertility associated with the use of finasteride, a drug commonly used for hair loss. The patients showed abnormal sperm concentration and motility while using finasteride, but these alterations were completely reversed or improved after the interruption of finasteride treatment. The article suggests that finasteride may not dramatically change the spermatogenesis process in healthy men, but in patients with other problems contributing to infertility, the negative influence of finasteride noted by others might be amplified. Further research is needed to fully understand the impact of finasteride on fertility in humans.
237 citations,
December 2001 in “Urology” Blocking the enzyme 5α-reductase can shrink the prostate and help treat enlarged prostate issues.
129 citations,
October 2000 in “British Journal of Dermatology” Finasteride helps increase hair growth in men with hair loss.
104 citations,
October 1999 in “The Journal of Urology” Finasteride doesn't harm male fertility or sperm quality, but may slightly reduce ejaculate volume.
37 citations,
January 1991 in “Reproductive Toxicology” Finasteride reduces male rat fertility by causing issues with copulatory plug formation.
Dutasteride did not change rat spermatogenesis or oxidative stress but needs more research.
195 citations,
February 2007 in “The Journal of Clinical Endocrinology and Metabolism” Dutasteride and finasteride may reduce sperm count and volume but don't affect movement or shape; effects are reversible after stopping.
34 citations,
January 2004 in “Revista do Hospital das Clínicas” Finasteride may worsen infertility in men with existing issues, but stopping it can improve sperm health.
30 citations,
August 1992 in “The Journal of Clinical Endocrinology and Metabolism” Finasteride doesn't affect hormone levels in normal men.
