Hyperprolactinemia refers to an overbundance of the hormone prolactin. Subfertility as a result of this increased level can occur in both men and women, and is found in up to one-third of women experiencing amenorrhea.

Hyperprolactinemia is considered a pituitary disorder. Prolactin secretion (by the pituitary) is triggered by the release of thyrotropin-releasing hormone (TRH).

Prolactin is secreted by the pituitary gland, and in pregnant women, is used by the body to prepare breasts for milk production. The term "lactating", often used to refer to nursing mothers, comes from "prolactin." Galactorrhea, noticeable milk production from the breasts during times other than when nursing, is commonly associated with hyperprolactinemia.

Why does hyperprolactinemia occur?

  • Common cause -- pituitary tumors, usually prolactinomas which are under 10 mm in diameter
  • Common cause -- primary hypothyroidism, due to increased TRH resulting in increased TSH & prolactin
  • Ingestion of certain drugs, including phenothiazines, certain high blood pressure meds (especially a-methyldopa), tranquilizers and opioids, antinausea drugs, oral contraceptives
  • Chronic kidney failure and other medical conditions
  • Unexplained in about 30 percent
Also associated with:
  • hypogonadotropinism and hypogonadism