Hypothalamic–pituitary–gonadal axis

The hypothalamic–pituitary–gonadal axis (HPG axis, also known as the hypothalamic–pituitary–testicular/ovarian axis) refers to the hypothalamus, pituitary gland, and gonadal glands as if these individual endocrine glands were a single entity. Because these glands often act in concert, physiologists and endocrinologists find it convenient and descriptive to speak of them as a single system.