“The pituitary is the leader in the endocrine orchestra.”
— Walter Langdon-Brown
What is the pituitary gland?
The pituitary is a pea-sized gland found inside a bony hollow in the base of your skull.
It sits underneath your brain, level with the bridge of your nose.
It is also known as the adenohypophysis.
The pituitary is known as the "master gland" due to its important job.
It controls every cell in the body, such as growth, fertility, stress response and water balance.
The pituitary controls hormones essential for keeping you alive and important bodily functions.
The pituitary is split into two parts: the front part known as the anterior and the back part is known as the posterior. Like the other parts of your body, it relies on blood to carry oxygen to keep it alive.
The anterior part of the pituitary does not have a direct blood supply of its own, so it relies on blood coming down a very narrow stalk from the hypothalamus, at the base of the brain, then through the posterior part.
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Pituitary in pregnancy
When you are pregnant, your pituitary gland swells in size. This is so that it can release the hormones needed to grow your baby.
It can double in size; imagine a pea becoming the size of a grape!
The pituitary may become over-enlarged due to an autoimmune reaction. This is known as Lymphocytic Hypophysitis. Cells cannot function as they should because the immune system attacks them.
The anterior pituitary is vulnerable to damage, particularly when it is enlarged in pregnancy. This is because it relies on blood flow through a narrow stalk from the hypothalamus.
Cells in the pituitary can become damaged and unable to function if they do not receive enough oxygenated blood. This might occur if you lose a lot of blood or have very low blood pressure. This means that the cells cannot perform their job of releasing hormones.
Postpartum Hypopituitarism is the medical term used to describe damage to the pituitary gland in or after childbirth, where there are hormone deficiencies. Sheehan’s Syndrome is another term used.
Scientists believe more research is needed to better understand why a pituitary gland may be damaged in pregnancy or childbirth. It is thought there may be many factors involved.
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