17) {LUTEAL PHASE} The final phase of the menstrual cycle is called the luteal phase. During the luteal phase, the follicle morphs into a mass of cells called the corpus luteum. The corpus luteum releases progesterone, which will keep the uterine wall thick and ready for a fertilized egg to implant.
18 {FOLLICULAR PHASE} During the follicular phase (or proliferative phase), follicles in the ovary mature under the control of estradiol. Follicle-stimulating hormone (FSH) is secreted by the anterior pituitary gland beginning in the last few days of the previous menstrual cycle.
