North American Registry of Midwives (NARM) Practice Exam

Which hormone is primarily responsible for the development of Graafian follicles?

1. Luteinizing hormone

2. Follicle-stimulating hormone

3. Progesterone

4. Testosterone

The correct answer is: Follicle-stimulating hormone

The hormone primarily responsible for the development of Graafian follicles is follicle-stimulating hormone (FSH). FSH is produced by the anterior pituitary gland and plays a crucial role in regulating the menstrual cycle and stimulating the growth and maturation of ovarian follicles. During the follicular phase of the menstrual cycle, FSH promotes the growth of several follicles in the ovaries, leading to one dominant follicle, also known as the Graafian follicle, that will eventually release an egg during ovulation. The increase in FSH levels encourages the follicles to produce estrogen, which further prepares the uterine lining for potential pregnancy and signals the pituitary gland to reduce FSH production once the dominant follicle has developed adequately. In contrast, luteinizing hormone (LH) plays a different role primarily in triggering ovulation and supporting the formation of the corpus luteum after the follicle has released an egg. Progesterone is involved in maintaining pregnancy and preparing the endometrium but is not responsible for the development of the follicles. Testosterone, while important in the body, does not influence the development of Graafian follicles directly as FSH does.