prolactin

American  

[proh-lak-tin] / proʊˈlæk tɪn /

noun

Biochemistry.

1. an anterior pituitary polypeptide hormone that stimulates lactation by the mammary glands at parturition in mammals, the activity of the crop in birds, and in some mammalian species the production of progesterone by the corpus luteum.

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prolactin British  

/ prəʊˈlæktɪn /

noun

1. Also called: luteotrophin.   luteotrophic hormone.  a gonadotrophic hormone secreted by the anterior lobe of the pituitary gland. In mammals it stimulates the secretion of progesterone by the corpus luteum and initiates and maintains lactation See also follicle-stimulating hormone luteinizing hormone

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prolactin Scientific  

/ prō-lăk′tĭn /

1. A protein hormone secreted by the anterior portion of the pituitary gland that stimulates and maintains the secretion of milk in mammals.

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Etymology

Origin of prolactin

First recorded in 1930–35; pro- ¹ + lact- + -in ²

Example Sentences

See Examples For:

prolactin

Several hormones can spike in men when they become dads, including oxytocin, linked to better relationship quality; vasopressin, associated with emotional bonding; and prolactin, which promotes lactation in women and caregiving behavior in guys.

From Los Angeles Times ● Jun. 10, 2026

“Prolactin also rises to support milk production. But, in order for prolactin to increase, dopamine must drop.”

From Slate ● Mar. 15, 2026

"Thus, growth hormone and prolactin could be considered as new adjuvants to promote immune responses following vaccination, especially in aged people, who typically display reduced levels of these hormones during sleep."

From Science Daily ● Mar. 8, 2024

Though changes in hormones such as prolactin, estrogen, and progesterone can occur, there’s no clear pattern or elevation of hormone levels associated with the condition, Clark says.

From National Geographic ● Sep. 11, 2023

The mammary gland is composed of milk-transporting lactiferous ducts, which expand and branch extensively during pregnancy in response to estrogen, growth hormone, cortisol, and prolactin.

From Textbooks ● Jun. 19, 2013