Answer:
The follicular phase
Explanation:
The follicular phase of the ovarian cycle (days 1-14) coincides with the menses and proliferative phases of the uterine cycle.
During the follicular phase, the increased levels of follicle-stimulating hormone (FSH) from the anterior pituitary trigger the development of several follicles.
However, only one of these follicles continues the development and secretes estrogen. Under the influence of higher levels of estrogen, the endometrium of the uterus thickens and becomes more and more vascular and glandular.
