The corpus luteum is a vital yet temporary organ that plays a crucial role in fertility during the luteal phase. It is an endocrine structure in females existing within the ovary once the ovarian follicle has released a mature ovum during ovulation. The secretion of hormones from the corpus luteum will stop within 14 days after ovulation if the oocyte is not fertilized. It then degenerates into a scar within the ovary, known as a corpus albicans. The role of the corpus luteum is the maintenance of a uterine environment that allows for implementation and pregnancy. This occurs by the release of pregnancy-related hormones and regulation of the hypothalamic-pituitary access through inhibition of gonadotropin-releasing hormone from the hypothalamus, which in turn decreases the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) released from the anterior pituitary. The primary hormone produced by the corpus luteum is progesterone, but it also produces inhibin A and estradiol. In the absence of fertilization, the corpus luteum will regress over time. A corpus luteum develops each time a woman ovulates so that a woman will produce a corpus luteum numerous times throughout her lifetime.