Also called lactogenic hormone, is a hormone produced and secreted into the bloodstream by the anterior pituitary gland in your brain. It stimulates the development and growth of the mammary glands or breast in females along with some other hormnes especially in pregnancy. After delivery, it is essential for the initiation and maintenance of milk production. It’s synthesis and release from the pituitary gland are mediated by the central nervous system in your brain in response to suckling by the infant. When suckling or its mechanical equivalent ceases, prolactin secretion slows and milk production ceases.