Which hormone is responsible for initiating the growth of ovarian follicles in women?

Follicle stimulating hormone, or FSH, plays a crucial role in the menstrual cycle and is specifically responsible for initiating the growth and maturation of ovarian follicles in women. FSH is produced by the anterior pituitary gland and acts on the ovaries, stimulating the growth of multiple follicles during the follicular phase of the menstrual cycle. As these follicles grow, they secrete estrogen, which contributes to the regulation of the menstrual cycle and prepares the uterine lining for potential implantation of a fertilized egg.

While luteinizing hormone does play a significant role in the menstrual cycle, particularly in triggering ovulation, it is not the hormone responsible for the initial growth of ovarian follicles. Progesterone is primarily involved in maintaining pregnancy and preparing the uterine lining, and it does not initiate follicular growth. Gonadotropin-releasing hormone, produced in the hypothalamus, stimulates the release of FSH and luteinizing hormone from the pituitary but does not directly initiate follicular growth itself. Thus, FSH is the primary hormone responsible for initiating ovarian follicle development in women.