Effects of the chronic use of finasteride on testicular weight and spermatogenesis in Wistar rats.

OBJECTIVE

To evaluate spermatogenesis in rats chronically exposed to finasteride, as the recent use of finasteride in young men to prevent hair loss has raised concerns about chronic use and fertility.

MATERIALS AND METHODS

Male Wistar rats (4 months old) were selected and divided into two groups. Group 1 (17 rats) received a finasteride suspension of 2 mg/kg/day in saline solution, 5 days/week for 10 months; group 2 (eight rats of the same age) were treated with placebo for the same period. At the end of the exposure the testes were weighed and processed for histological analysis. Spermatogenesis was evaluated as the mean number of seminiferous tubules with and without spermatozoids in their lumen, in five random fields on the same slide. Student's t-test was used to assess differences in the groups.

RESULTS

In group 1, the mean (sd) weight of the testes was 1.55 (0.29) g and in group 2 1.58 (0.34) g (P>0.05). The histological analysis showed a mean of 13.35 (1.66) seminiferous tubules per field and 1.20 (3.30) tubules with no spermatozoids in group 1; in group 2 the respective values were 13.53 (1.46) and 0.06 (0.14) (P>0.05).

CONCLUSION

Finasteride had no detectable effects on the quantitative and qualitative analysis of spermatogenesis in rats.