Galactorrhea: a milky breast discharge occurring at anytime other than during normal breast feeding. Galactorrhea is most often seen in women with hyperprolactinemia (high blood levels of prolactin), especially in those with prolactinoma or other pituitary-related tumors. Galactorrhea often occurs in association with amenorrhea (absence of menstrual periods) because of the effect of high prolactin on LH and FSH release from the pituitary gland. Rarely men may also experience galactorrhea. Learn more.