What Happens During the Preovulatory Follicle Stage?
During this stage, the dominant follicle grows rapidly in response to increased levels of Follicle-Stimulating Hormone ([FSH]()). This growth leads to the production of high levels of [estradiol](), a form of estrogen. The rising estrogen levels stimulate the thickening of the [endometrium]() in preparation for potential [implantation]() of an embryo.
