Prolactin (Lactogenic hormone) Serum Adult: 0-20 ng/ml Pregnancy Third trimester: 34-306 ng/ml Lactating mother: < 40 ng/ml To evaluate oligomenorrhea, amenorrhea, or Galactorrhea To assist in the diagnosis of pituitary gland or hypothalamic dysfunction Hypothalamus -- pituitary disease (Sarcoidosis, Metastatic Cancer) Prolactin-secreating pituitary tumor Acromegaly Hypothyroidism Anorexia nervosa Adrenal insufficiency Pituitary infarction or necrosis Alcohol intake Failure to fast in the pretest period Recent radioactive isotope scan Warming of the specimen Hemolysis Sleep disturbance