How does the corpus luteum influence the menstrual cycle?

The corpus luteum is a hormone-secreting body that forms in the ovary from the remains of a follicle following ovulation. Its primary role in the menstrual cycle is to regulate the uterine environment through the secretion of estrogens and progesterone.12

During the secretory phase, these hormones induce changes in the endometrium, causing the glands to become tortuous and the tissue to thicken, which prepares the uterus for the potential implantation of a fertilized ovum.12

If fertilization does not occur, the corpus luteum becomes inactive and degenerates. This leads to a withdrawal of estrogen and progesterone, which triggers the breakdown of the endometrial lining and the onset of menstruation. While the menstrual cycle continues until menopause, the corpus luteum's function is strictly tied to the recurring preparation of the uterus for pregnancy during the reproductive years.12