What phase does Days 14-28 of the menstrual cycle represent?

Days 14-28 of the menstrual cycle represent the luteal phase, which is characterized by the presence of the corpus luteum, a structure formed from the follicle after ovulation. During this phase, the corpus luteum secretes progesterone and estrogen, hormones that prepare the endometrium for a potential implantation of a fertilized egg.

If fertilization does not occur, the corpus luteum degenerates, leading to a decrease in hormone levels, which ultimately triggers menstruation. The luteal phase typically lasts around 14 days and is crucial for establishing a supportive environment for a possible pregnancy.

In contrast, the follicular phase occurs earlier in the cycle, leading up to ovulation, while the proliferative and secretory phases refer more specifically to changes in the endometrium associated with estrogen and progesterone levels, respectively.