High pituitary prolactin is commonly found in the following situations: 1. Physiological increase: It is increased when there is some local stimulation in the body, during physiological periods, menstruation, lactation and other physiological situations. The secretion of hormone levels is also increased during nighttime sleep; 2. Due to systemic diseases: prolactin levels are increased when kidney function is impaired and liver function is impaired. In addition, if there is shingles on the chest and back, and if there is hyperplasia and pain in the breast, the local painful stimulation will also lead to increased prolactin; 3. Prolactinoma: If the cells that secrete prolactin proliferate into a tumor state, it is called a prolactinoma, which can also bring about hyperprolactinemia.