Which statement about the uterine cycle is true?

Which statement about the uterine cycle is true?

• A. It includes proliferative, secretory, ischemic, and menstrual phases.
• B. It consists of only two phases.
• C. It has no hormonal influence.
• D. It is identical to the ovarian cycle.

Answer: (A)

The uterine cycle is a hormone-driven sequence of changes in the endometrium that prepares the lining for possible pregnancy. It typically includes four phases: menstrual, proliferative, secretory, and ischemic. During the menstrual phase, the functional endometrial layer sheds when progesterone and estrogen levels fall. In the proliferative phase, rising estrogen from the growing ovarian follicle stimulates rebuilding and thickening of the endometrium. After ovulation, the secretory phase features progesterone-driven maturation of the glands and secretions to nourish a potential embryo. If pregnancy does not occur, hormone levels fall again during the ischemic (pre-menstrual) phase, leading to breakdown and the start of a new cycle. This is why the statement describing those four phases is true. The cycle is not limited to two phases, it does involve hormonal control, and it is coordinated with, but not identical to, the ovarian cycle (which has follicular, ovulation, and luteal phases).

The uterine cycle is a hormone-driven sequence of changes in the endometrium that prepares the lining for possible pregnancy. It typically includes four phases: menstrual, proliferative, secretory, and ischemic. During the menstrual phase, the functional endometrial layer sheds when progesterone and estrogen levels fall. In the proliferative phase, rising estrogen from the growing ovarian follicle stimulates rebuilding and thickening of the endometrium. After ovulation, the secretory phase features progesterone-driven maturation of the glands and secretions to nourish a potential embryo. If pregnancy does not occur, hormone levels fall again during the ischemic (pre-menstrual) phase, leading to breakdown and the start of a new cycle.

This is why the statement describing those four phases is true. The cycle is not limited to two phases, it does involve hormonal control, and it is coordinated with, but not identical to, the ovarian cycle (which has follicular, ovulation, and luteal phases).