metestrus

Metestrus is a phase in the reproductive cycle of female mammals, occurring after estrus (heat) and characterized by the regression of the reproductive tract to its normal state. This period follows ovulation and the subsequent decline of the corpus luteum, which produces progesterone. If fertilization does not occur, the uterine lining, which had thickened in preparation for implantation, begins to recede. Metestrus may be followed by anestrus, a non-reproductive period, or by diestrus, a brief quiescent phase before the cycle potentially restarts with proestrus. This cyclical process is regulated by hormones from the pituitary gland and ovaries, with estrus being the period when the female is receptive to mating.1234