The pituitary is an endocrine (hormone-producing) gland that sits just beneath the base of the brain, behind the bridge of the nose. It is very small – only about the size of a pea. The pituitary gland is very important as it takes messages from the brain (via a gland called the hypothalamus) and uses these messages to produce hormones that affect many parts of the body, including stimulating all the other hormone-producing glands to produce their own hormones. For this reason it is often referred to as the ‘master gland’.

The pituitary gland has two parts. The anterior (or front) pituitary produces hormones that affect the breasts, adrenals, thyroid, ovaries and testes, as well as several other hormones. The main glands affected by the posterior (or rear) pituitary are the kidneys.