MICROANATOMY

Detailed explanation-1: -If the egg is not fertilized, the corpus luteum degenerates and no longer produces progesterone, the estrogen level decreases, the top layers of the lining break down and are shed, and menstrual bleeding occurs (the start of a new menstrual cycle).

Detailed explanation-2: -The luteal phase lasts for about 14 days. After the egg has left the follicle, your corpus luteum starts to form from the materials that made up that follicle. Your corpus luteum produces the hormones estrogen and progesterone. Making progesterone is the corpus luteum’s most important job, though.