Related Experiment Video
Updated: Jun 4, 2026

Flow Cytometric Analysis of Biomarkers for Detecting Human Sperm Functional Defects
Published on: April 21, 2022
Finasteride-induced secondary infertility associated with sperm DNA damage
Hin Yu Vincent Tu1, Armand Zini
1Division of Urology, Department of Surgery, McGill University, Montreal, Quebec, Canada.
Objective:
To report a case of low-dose finasteride-induced secondary infertility with associated elevated sperm DNA fragmentation index (DFI) and otherwise normal semen parameters.
Design:
Case report.
Setting:
University hospital.
Patient(S):
A 48-year-old man on low-dose finasteride and his 37-year-old wife with normal menses and normal gynecologic exam.
Intervention(S):
Determination of sperm DFI and discontinuation of low-dose finasteride.
Main Outcome Measure(S):
Sperm DFI.
Result(S):
The sperm DFI done a year earlier was 30%. This value was unchanged when repeated 2 months later. The patient was advised to stop finasteride. Three months after discontinuing the finasteride, the DFI decreased to 21% and subsequent DFI after another 3 months improved to 16.5%. To date, there is still no documented full-term pregnancy or live birth.
Conclusion(S):
The significant reduction in DFI within 3 months of finasteride cessation and continued improvement suggests a causal link between finasteride and sperm DNA damage. We hypothesize that low-dose finasteride may exert a negative influence on sperm DNA integrity, resulting in increased pregnancy losses. We suggest that in infertile men using finasteride, sperm DFI should be measured in addition to semen parameters, and a trial of discontinuation of finasteride may be warranted.
Related Concept Videos
Infertility in Males
Spermatogenesis
Infertility in Females
Endometriosis, a condition characterized by abnormal growth of endometrial...
Disorders of the Male Reproductive System
Prostate disorders are another major concern. These conditions can impair urinary flow due to the prostate's location around the urethra. Symptoms...
Meiosis II
DNA Damage Can Stall the Cell Cycle