What characterizes the metestrus stage?

The metestrus stage is characterized by the physiological changes that occur after ovulation. During this phase, the body prepares for the possibility of pregnancy following ovulation. The key feature of metestrus is that it follows estrus (the heat period) and is marked by the presence of the corpus luteum, which forms from the follicle that released the egg during ovulation.

This stage is essential for the establishment of pregnancy; if fertilization occurs, the corpus luteum produces hormones such as progesterone to support pregnancy. If fertilization does not take place, the corpus luteum eventually degenerates, leading the animal back into the anestrus phase. Thus, the defining characteristic of metestrus is indeed the occurrence of ovulation, which sets the stage for either fertilization or the subsequent reproductive cycle phases.