What term is used to describe the period after ovulation during which the corpus luteum is active?

The period following ovulation when the corpus luteum is active is referred to as diestrus. During diestrus, the corpus luteum produces progesterone, which plays a critical role in preparing the uterus for potential pregnancy. If fertilization does not occur, the corpus luteum will eventually regress, leading to a drop in progesterone levels and the onset of the next estrous cycle.

In contrast, if one considers the periods named in the other options, anestrus is characterized by a lack of reproductive activity and can be seen as a resting phase in the reproductive cycle. Metestrus typically refers to the period immediately following estrus and before diestrus, when hormonal changes start to occur but before the corpus luteum has fully developed. Proestrus is the phase preceding estrus, focusing on the maturation of follicles and preparation for mating, rather than the activity of the corpus luteum. Therefore, diestrus distinctly encapsulates the function and significance of the corpus luteum during this post-ovulation phase.