Daily oral desogestrel combined with testosterone pellets for 8 weeks in healthy men is associated with suppression of luteinizing hormone and follicle-stimulating hormone, with no significant differences observed between doses of 75, 150, or 300 micrograms.

A synthetic hormone in the pill binds to brain receptors that control hormone signals, stopping the brain from telling the pituitary to release two key hormones. At the same time, a testosterone implant floods the body with androgen, which directly tells the pituitary and brain to stop making those same hormones. Together, this double signal shuts down the production of luteinizing hormone and follicle-stimulating hormone, regardless of how much of the pill is taken, because the brain and pituitary are already fully silenced.