During which phase does the follicle mature and prepare to release an egg?

The follicular phase is the stage in the menstrual cycle during which follicles in the ovaries mature, leading to the development of a dominant follicle that ultimately prepares to release an egg. This phase begins on the first day of menstruation and typically lasts until ovulation occurs.

During the follicular phase, the body produces increased levels of follicle-stimulating hormone (FSH), which stimulates the growth of these follicles. As the follicles develop, they secrete estrogen, which plays a crucial role in preparing the uterine lining for a possible pregnancy and signaling further maturation. The peak of estrogen production eventually leads to a surge in luteinizing hormone (LH), triggering ovulation—the release of the egg from the mature follicle.

In contrast, the luteal phase occurs after ovulation, when the ruptured follicle transforms into the corpus luteum and produces progesterone to support the uterine lining. The menstrual phase is characterized by the shedding of the uterine lining when fertilization does not occur, while ovulation is the process of releasing the egg itself, rather than the maturation of the follicle. Therefore, the correct answer, highlighting the period of follicle maturation and readiness for ovulation, is the follicular phase.