The anterior pituitary regulates several physiological processes, including stress, growth, reproduction, and lactation.

Proper functioning of the anterior pituitary and of the organs it regulates can often be ascertained via blood tests that measure hormone levels.

The pituitary gland sits in a protective bony enclosure called the sella turcica (Turkish chair/saddle).

However, in humans, the intermediate lobe is but a few cell layers thick and indistinct; as a result, it is often considered part of the anterior pituitary.

However, it has been seen to be important in receiving the endocrine signal in the form of TSHB (a β subunit of TSH), informing the pars tuberalis of the photoperiod (length of day).

The expression of this subunit is regulated by the secretion of melatonin in response to light information transmitted to the pineal gland.

The anterior pituitary is derived from the ectoderm, more specifically from that of Rathke's pouch, part of the developing hard palate in the embryo.

Its formation from the soft tissues of the upper palate contrasts with the posterior pituitary, which originates from neuroectoderm.

[6] The anterior pituitary contains five types of endocrine cell, and they are defined by the hormones they secrete: somatotropes (GH); lactotropes (PRL); gonadotropes (LH and FSH); corticotropes (ACTH) and thyrotropes (TSH).

[12] Gonadotropes, primarily luteinising hormone (LH) secreted from the anterior pituitary stimulates the ovulation cycle in female mammals, whilst in the males, LH stimulates the synthesis of androgen which drives the ongoing will to mate together with a constant production of sperm.

[6] Main article Hypothalamic-pituitary-adrenal axis The anterior pituitary plays a role in stress response.

For example, acromegaly results from excessive secretion of growth hormone (GH) often being released by a pituitary adenoma.

The anterior pituitary is also known as the adenohypophysis, meaning "glandular undergrowth", from the Greek adeno- ("gland"), hypo ("under"), and physis ("growth").