The pituitary gland, located at the base of the brain, is an extremely important endocrine gland in the human body, capable of secreting a variety of hormones that directly or indirectly regulate most of the physiological functions of the body. Pituitary fullness may have the following conditions: First, physiological hypertrophy of the pituitary gland, such as women during pregnancy and childbirth, the pituitary gland will increase in size, appearing physiological pituitary fullness. Second, pituitary hyperplasia or pituitary adenoma, when there is pituitary hyperplasia or pituitary adenoma, fullness of the pituitary gland can occur. Pituitary fullness is not always a pituitary tumor, but it may be a pituitary microadenoma, so further examination is needed, and pituitary function tests should be improved if necessary. Third, severe hypothyroidism can also present with pituitary fullness. Therefore, if the pituitary MRI suggests pituitary fullness, pituitary function tests and thyroid function tests should be improved as much as possible to clarify the cause and do regular review.