During which phase does the endometrium begin to proliferate?

During which phase does the endometrium begin to proliferate?

• A. Early follicular
• B. Mid follicular
• C. Late follicular
• D. Early luteal

Answer: (B)

Rising estrogen from the developing ovarian follicles stimulates the endometrium to thicken by cell proliferation. As the follicular phase progresses and estrogen levels climb, this proliferative change becomes evident, with the lining becoming thicker and glands more developed by mid-follicular, preparing the uterus for potential implantation. After ovulation, progesterone from the corpus luteum promotes a secretory transformation rather than further proliferation.

Rising estrogen from the developing ovarian follicles stimulates the endometrium to thicken by cell proliferation. As the follicular phase progresses and estrogen levels climb, this proliferative change becomes evident, with the lining becoming thicker and glands more developed by mid-follicular, preparing the uterus for potential implantation. After ovulation, progesterone from the corpus luteum promotes a secretory transformation rather than further proliferation.