Elevations in prolactin may cause amenorrhea or galactorrhea. Amenorrhea without galactorrhea is associated with hyperprolactinemia in approximately 15% of women. In patients with both galactorrhea and amenorrhea, approximately two-thirds will have hyperprolactinemia; of those, approximately one-third will have a pituitary adenoma. In more than one-third of women with hyperprolactinemia, a radiologic abnormality consistent with a microadenoma (<1 cm) is found. Normal Prolactin levels Males: 2-20 ng/mL Females (non-pregnant): 2-30 ng/mL Pregnant females: 10-200 ng/mL A prolactin level of more than 200 ng/mL is usually due to a pituitary tumour and requires pituitary evaluation