It has been observed that blood testosterone levels in men oscillate with a period of 2 to 3 hours. One simple, deterministic model was proposed to describe this phenomenon, but it was recently proved that the model has a globally stable fixed point. Therefore, the deterministic model cannot observe oscillations. We will take a closer look at this model from a different physical basis in which intrinsic fluctuations are considered. It turns out that sustained oscillations do arise in the continuous-time, discrete-state stochastic model.