Fig. 26. Diagram illustrating the important consequences of the increased levels of follicle-stimulating hormone(FSH) in the early follicular phase of the human menstrual cycle on the growth and development of the dominant follicle. Estradiol produced by the dominant follicle is physiologically coupled to the mechanisms governing suppressor of FSH at the mid-follicular phase and for the stimulation of luteinizing hormone (LH) secretion at mid-cycle. (From Erickson GF: Analysis of follicle development and ovum maturation. Semin Reprod Endocrinol 4:233, 1986.)