Hyperprolactinemia

Abstract

Prolactin (PRL) is a hormone best known by its function for preparing mammary glands for lactation and for inducing hypogonadism in the postpartum period, essential for directing mother care toward the newborn. In clinical practice, hyperprolactinemia is an important cause of hypogonadism and infertility, especially among young women, and the correct diagnosis is essential for the proper therapeutic management. In addition to this well-established role of PRL, there are more than 300 known autocrine and paracrine functions in different species, mainly related to fluid balance, growth, immunoregulation, and protection and, more recently, related to tumorigenesis. In this chapter, we discuss the classical actions of PRL, the pathophysiology of hyperprolactinemia, and its differential diagnosis and treatment.