The pituitary gland is a pea-sized structure located at the base of the brain, just below the hypothalamus, to which it is attached via nerve fibers. It is part of the endocrine system and produces critical hormones, which are chemical substances that control various bodily functions.

The pituitary is divided into three sections: the anterior, intermediate, and posterior lobes. The anterior lobe is mainly involved in development of the body, sexual maturation, and reproduction. Hormones produced by the anterior lobe regulate growth, and stimulate the adrenal and thyroid glands, as well as the ovaries and testes. It also generates prolactin, which enables new mothers to produce milk.

The intermediate lobe of the pituitary gland releases a hormone that stimulates the melanocytes, cells which control pigmentation — like skin color — through the production of melanin.

The posterior lobe produces antidiuretic hormone, which reclaims water from the kidneys and conserves it in the bloodstream to prevent dehydration. Oxytocin is also produced by the posterior lobe, aiding in uterine contractions during childbirth and stimulating the production and release of milk.