There is nothing such as Corpus Lyceum. If you wanted to know about Corpus Luteum, it is a hormone secreting body in the female reproductive system. It is yellow in colour and is formed in the site of the follicle or sac that has matured and released its ovum during the process of ovulation. Corpus luteum secretes estrogens and progesterone. Progesterone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. If the egg is not fertilized, the corpus luteum becomes inactive 10-14 days and menstruation occurs.