According to the sources, the human menstrual cycle consists of several phases: the menstrual phase, the follicular (proliferative) phase, the ovulatory phase, and the luteal (secretory) phase . During the proliferative phase, primary follicles grow into fully mature Graafian follicles, and the uterine endometrium regenerates . Ovulation occurs at the midpoint of the cycle (around day 14), triggered by a surge in LH and FSH . This event takes place precisely at the end of the proliferative phase, just before the ruptured follicle transforms into the corpus luteum to begin the secretory phase .