Finasteride and Male Fertility

Introduction to Finasteride Effects

Finasteride at 5 mg/day is associated with reduced semen volume, while the evidence for the 1 mg/day dose used for hair loss is less conclusive regarding semen parameters, as noted by the American Urological Association 1
The 5 mg/day dose has more consistent evidence showing reduced semen volume, according to the American Urological Association 1, 2
Sexual side effects, including reduced ejaculate volume, are consistently higher with finasteride than placebo, though the absolute magnitude is small, with a 2-4% increase in reported events 2, 3

Finasteride can reduce semen volume and potentially affect other semen parameters, particularly at the 5 mg dose, with the American Urological Association noting the association between finasteride and reduced semen volume 1
The reduction in ejaculate volume is likely related to finasteride's effects on prostate size and secretory function, although the exact mechanism is not fully understood 1

For men actively trying to conceive, consideration of discontinuation of finasteride if fertility issues arise is recommended, allowing sufficient time for complete reversal of effects, although the optimal duration is not well established 1
For men with pre-existing fertility issues, exercise caution when using finasteride, especially at higher doses, and consider baseline semen analysis before starting therapy, as suggested by the American Urological Association 1
For men on long-term therapy, awareness that normalization or improvement of seminal quality has been reported after discontinuation is important, with the American Urological Association noting the potential for reversible effects 1