21. MENSTRUAL CYCLE (CONTINUED) FSH and LH released Uterine lining (endometrium) is shed, maturation of follicle Follicle secretes estrogen Lining of the uterus increase in thickness ovulation LH change remain of the follicle into a corpus luteum Corpus luteum produce estrogen and progesteron Uterine lining (endometrium) increase in thickness Fertilization doenst occur, corpus luteumdegenerates, progesteron reducted