Suppression of Spermatogenesis by Exogenous Testosterone.
Level 5 - mechanism / opinion, no new human data
Narrative review describing physiological mechanisms and existing literature without systematic methodology.
PubMed 33292112 · doi:10.2174/1381612826666201207104340
What was done
This paper reviews the hormonal regulation of spermatogenesis by the hypothalamic-pituitary-gonadal axis and summarizes literature on the suppression of male fertility by exogenous testosterone and subsequent recovery after cessation.
What was found
No quantitative data are reported in the abstract. Exogenous androgens exert negative feedback on the hypothalamic-pituitary-gonadal axis, reducing FSH and LH and causing partial or complete cessation of spermatogenesis. While studies indicate sperm concentrations eventually return to baseline after stopping treatment, the duration required for recovery and whether recovered counts are sufficient for fertility remain unresolved.
Why it matters
It highlights the contraceptive effect of exogenous testosterone on male fertility while identifying persistent gaps in predicting the timing and adequacy of post-cessation spermatogenic recovery.
Limits
The abstract presents a narrative overview without primary empirical data, sample sizes, or systematic review methods. Confounding variables such as dosage, duration of use, and baseline fertility status are not detailed.